Growing up in Nara, Japan, one food that was a constant in my home was tofu. It’s truly been a lifelong staple. 

When I was a baby, once I could eat solids, my mom commonly prepared two dishes for me — one was a mix of tofu, rice porridge, sweet potato, kabocha (squash), and nori (seaweed) paste, and the other was miso soup with rice porridge.

I carried on that culinary tradition with my two kids when they were small. I never bought any ultra-processed baby food; instead I opted for tofu. It saved me time, money and stress, and it was a way for us to connect with our roots while living in the U.S.

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When we arrived here in 1994, tofu was harder to come by. If I could only find shelf-stabilized packaged versions, I kept about two dozen of them in the house at any given time. Even today, I always have several packs of tofu in my refrigerator.

In Japan, tofu is enjoyed by folks of all ages. My in-laws are 95 and 88 years old. They still live in Nara, and have tofu, natto (fermented soybeans) and miso soup every day. They attribute their longevity and immunity, in part, to that daily routine.

Here is why tofu is my No. 1 kitchen must-have.

Tofu is traditionally made from soybeans and nigari, the liquid that remains after removing the salt from seawater. In the U.S., calcium sulfate is often used as the main coagulant. 

Either way, tofu contains all the essential amino acids that meat, poultry, eggs, fish and dairy do — but without cholesterol, since it is plant based.

It also is rich in calcium, iron, vitamins, fiber and isoflavones, a type of plant estrogen. 

Studies have shown that the consumption of tofu can help reduce the risk of heart disease, fight cancer and reduce the risk of bone loss. 

It takes 70.6 kilograms of greenhouse emissions to produce just one kilogram of beef, but only 3.2 kilograms of emissions to produce the same amount of tofu.

I typically purchase 14 ounces of organic tofu for $2 or $3, which is often much less than the same amount of poultry or beef would cost me at the grocery store. 

To me, it is simple math. In the course of the week, if you were to swap out one or two beef burgers for a tofu burgers, you would feel better, pay less for groceries and do something small to help the environment. 

Tofu has a very natural, subtle flavor, so it can be matched with just about any cuisine or dish. Since it’s soft, you can also prepare it without a knife and cutting board.

As a nutritionist and cooking instructor, I am always developing new recipes, and tofu makes it very easy to experiment.

I serve tofu in a variety of ways: pan-fried or in soups and salads, in nimono (slow cooked roots and veggies), dumplings, veggie pancakes, vegan curry, burgers, cabbage rolls, mochi and ice cream, to name a few. 

My go-to lunch is a tofu miso soup with seasonal roots and leafy vegetables, seaweed, ginger and goji berries. Generally, I make a large pot and return to it throughout the week, serving it with multigrain rice, natto and nukazuke (pickles). 

My other perfect, simple meal is hiyayakko. It is cold tofu — usually the silken or soft variety — topped with nori, sesame seeds, ginger, shiso, scallions, natto and a little bit of soy sauce. If you prefer it warm, you can always pop it into the microwave for one to two minutes and then add your toppings. 

I often call tofu my best friend for happy living. I hope you are inspired to incorporate it into your kitchen, too. 

Michiko Tomioka, MBA, RDN, is a certified nutritionist and longevity expert. Born and raised in Nara, Japan, her approach focuses on a plant-based diet. She has worked in nutritional roles at substance recovery centers, charter schools and food banks. Follow her on Instagram @michian_rd. 

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This story is part of CNBC Make It’s Six-Figure Side Hustle series, where people with lucrative side hustles break down the routines and habits they’ve used to make money on top of their full-time jobs. Got a story to tell? Let us know! Email us at AskMakeIt@cnbc.com.

Emily Odio-Sutton remembers the exact moment she made her side hustle’s first sale.

She was in the lobby of a gymnasium at a kid’s birthday party near her home in Melbourne, Florida. One of her daughters had just taken a bite of Publix birthday cake, when her phone pinged: She’d sold a $22 T-shirt with a speech pathology-themed design on e-commerce marketplace Etsy.

“I can vividly see the cake, the balloons and remember thinking, ‘This can work,’” Odio-Sutton, 36, tells CNBC Make It.

Odio-Sutton started looking for a side hustle in 2022, after realizing her 9-to-5 job as an internal operations manager at a teachers’ book publishing company would prevent her from picking her daughter up from kindergarten. She started a print-on-demand shop, using Canva software to create designs for Etsy-friendly products like T-shirts and candles. Whenever a customer places an order, a manufacturer called Printify prints the design onto the product and ships it out for her.

Her Etsy store brought in $220,300 last year, according to documents reviewed by CNBC Make It. Odio-Sutton estimates that 30% of those sales are profit. She’s used her side hustle earnings to pay off her entire $20,000 student loan balance, start investing in the stock market, open college saving accounts for her daughters and take a cruise with her husband, she says.

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Last year, Odio-Sutton opened a second Etsy shop — selling downloadable event materials, like sign-up sheets and schedule templates — that’s brought in $17,200 in sales so far in 2024. And in June, she moved into a part-time role at the publishing company that makes $40 per hour, 20 hours per week.

She spends 10 hours per week on her Etsy shops, and often works from her laptop while sitting at her daughters’ gymnastics and swimming practice, she says. She’d prefer not to name her shops, to prevent potential copycats, she adds.

Here, Odio-Sutton discusses how to start a side hustle like hers, her formula for quick-selling designs and the biggest mistakes that she sees beginners make.

CNBC Make It: Do you think this side hustle is replicable? What are its starting costs?

Odio-Sutton: Yes, and I think that’s because there are so many ways to do it. Print-on-demand and digital-resource side hustles on platforms like Etsy have a built-in audience. It’s low risk, and you can really experiment with things and learn and take your time.

When I say low-risk, I mean you can launch a whole business for under $40. Canva Pro is $10 per month, Etsy charges $15 to open a shop and you can download research tools like eRank for $6 per month.

The biggest risk is time investment, because you do have to spend time to learn — and to get your shop established — to earn money.

A lot of people tout print-on-demand as a good source of passive income. What’s your workload like?

I have a good system for keeping my print-on-demand workload fairly light. I’ll batch design 10 candle labels one day, then make the listings for them on Etsy the next day.

My digital products shop, which has a lot of event-related printables like schedule templates and invitations, is almost entirely passive at this point. It’s limited customer service [compared to print-on-demand].

When you order a print-on-demand product on Etsy — for, say, a bachelorette party — you quickly see a lot of shops to choose from. Why do you think yours stands out?

You really can make a very good living by just having simple designs.

I’m not creative. I’m not a graphic designer. I follow what I’d call a template method: I do a lot of black-and-white designs, a lot of plain text. Then, if I have a template that sells really well, I’ll just go in and swap in new words.

I’ll go to ChatGPT and say, “Give me the top 100 careers” or “Top 100 hobbies in the U.S.” From there, I’ll do some design research on Etsy and Pinterest. My goal is more an emotional connection to the item, whether it’s funny, sentimental or relatable, as opposed to something really trendy.

I also Google memes. Like, I’ll look up HR memes. I had a social worker-themed candle about data and reports. You’re not going to find that at Target, or anywhere else.

You also work with a business, Gold City Ventures, to coach aspiring Etsy sellers. What’s the most common mistake most of your clients make?

First, they don’t narrow down enough. Is Etsy oversaturated? Yes, but only with generic listings. If you post a “mom” shirt, it’s going to be very hard to stand out. If you post a “twin mom Halloween” shirt, you’ll have a better chance.

The second piece is thinking you can post 20 designs, and that’s enough. You have to try, and fail, a lot, to figure what works. I have like 1,500 designs that I retired, because they never sold.

You have to invest time, research, experiment and stick with it to be successful.

This interview has been edited for length and clarity.

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When I first heard about the concept of passive income in my 20s, I laughed at the idea. Growing up, I had never met anyone who made money this way. 

My mindset completely changed after a conversation I had with a woman I really looked up to. She earned passive income from her real estate business. Seeing someone who I knew and trusted achieve this seemingly impossible goal, made me feel like I could do it too — although it took some time to finally get there myself. 

Four years ago, I was dealing with postpartum depression and struggling with a 9-to-5 job in higher education administration that didn’t bring me joy. I decided to start selling digital products like business templates and party games on Etsy. To my surprise and delight, the side hustle started to take off. 

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As a 36-year-old mom of two, I now make $10,000 in passive income or more every month from four passive income streams. 

Here is my best advice for starting a successful side hustle: 

Passive income doesn’t mean no work. It means front-loaded work that pays off later. No matter what kind of side hustle or passive income venture you are starting, thorough research can help you avoid costly mistakes.

Many people get excited about their first idea or opportunity and jump at it, without running the numbers. For example, when I first started on Etsy I made budgeting templates. I found that these didn’t sell very well because there was low demand and high competition. 

It was only after I took the time to research keywords and trends through Pinterest and Google Trends in the space, that I started to create more specific — and more successful — items for the shop. 

I highly recommend doing financial projections and understanding the expenses you’ll have before you ever spend a penny. One of the main reasons businesses fail, or never begin to thrive, is because they run out of money. 

In many cases, this problem can be predicted and dealt with proactively if you take the time early on to project your expenses.

Building passive income streams requires an investment of time, and many people underestimate how much time they need to allocate upfront. 

It’s easy to get distracted by day-to-day responsibilities (especially as a parent or full-time employee), but they’ll never come to fruition if you don’t make time to work on your passive income projects. 

Schedule dedicated time each week to focus on and stick to your passive income goals. For example, when I first started, I would spend 8-10 hours each week developing the skills I needed for my business, and I did this for months. 

Once I became serious, I started spending 20-30 hours a week actively creating products. Now I spend as a little as 15 minutes a day working on it, responding to messages and client inquiries. 

Studying successful passive income earners has taught me that success doesn’t come from quick wins but rather slow and steady progress toward a specific goal over time. In short, consistency is key.

The beauty of passive income is that it allows you to earn money without everyday active involvement. Automation is your best friend in this process. 

Because I sell digital products on Etsy, the platform comes with the ability to deliver automatically once a payment is processed. I use Convertkit to automate my email marketing.

Automation can save you time and help your income streams remain steady. I’ve found that failing to automate means more manual and mental work, and less freedom.

No one achieves success entirely on their own. Seeking help from mentors, financial advisors, and experts can significantly boost your chances of success. 

I dabbled with side hustles for years, but it wasn’t until I found a course by Gold City Ventures while listening to a podcast that taught me how to sell digital products on Etsy that I successfully created a passive income business.

After taking the course, I was able to get my business up and running and making money in about a month. It took about nine months before I started making passive income consistently. 

Surround yourself with people who have the knowledge and experience you lack. They can offer valuable insights, keep you accountable, and help you avoid pitfalls. 

Most importantly, they can encourage you when you feel like giving up.

Relying on a single source of income can leave you vulnerable to market fluctuations and unexpected changes. I’ve talked to so many business owners who are still recovering from the effects of the pandemic because they put all their eggs in one basket: Their business. 

My passive income portfolio includes stocks, bonds, real estate, and my small business, which sells digital products on Etsy and on my website. 

Diversification is essential to spreading the risk and increasing the chances of consistent returns.

I’ve seen countless people get stuck in the planning phase, waiting for the “right moment” that never comes. I’ve made that mistake too.

I credit studying positive psychology in grad school with helping me break free of those fears. Marilee Adams’s book “Change Your Questions, Change Your Life” helped me develop more of a growth mindset and change my internal dialogue from asking questions like, “Why bother?” to more optimistic ones like, “What can I learn?” 

The truth is, there’s no perfect time to start, and failure is always a possibility. However, the sooner you take action in a smart way, the sooner you can learn, and the higher your chances of reaping the rewards. 

Even small steps, like starting to research and educating yourself, can lead to significant progress over time. It’s vital not to let fear of failure or analysis paralysis keep you from starting your journey to passive income.

Rachel Jimenez is an entrepreneur, professor and mom of two, with a passion for helping others achieve their personal, professional and passive income goals. She runs an Etsy store as well as a blog, Money Hacking Mama, where she shares financial wisdom and practical advice for women navigating their careers, businesses and life.

Want to make extra money outside of your day job? Sign up for CNBC’s online course How to Earn Passive Income Online to learn about common passive income streams, tips to get started and real-life success stories.

If Dave Gilboa kept better track of his glasses, Warby Parker might not exist.

In 2008, Gilboa lost a $700 pair of Prada eyeglasses on a backpacking trip just before starting an MBA program at the Wharton School of the University of Pennsylvania. There, he met classmates — Neil Blumenthal, Andy Hunt and Jeff Raider — who understood his frustration.

Within months, the classmates were working on a solution that would eventually disrupt the nearly $150 billion global eyewear industry. They co-founded Warby Parker, a pioneering direct-to-consumer brand that’s sold millions of pairs of glasses, both online and in 269 brick-and-mortar stores across the U.S. and Canada.

Warby Parker brought in nearly $670 million in revenue last year. It currently boasts a market value of $1.79 billion, with Gilboa, 43, and Blumenthal, 44, serving as co-CEOs.

For most direct-to-consumer brands, the last, elusive piece of the puzzle is profitability, often due to razor-thin margins. Warby Parker is on the precipice: It’s making more money from brick-and-mortar stores than online, with in-store eye exams providing additional revenue, so it plans to steadily open more locations.

The simple strategy should push the company to a place of profitability and stability that has eluded so many of its compatriots, industry analysts say — probably as soon as next year.

“The need for glasses and contacts continues to grow and grow and grow,” Blumenthal tells CNBC Make It. “And we’re putting Warby Parker in a position to take advantage of that growth, to serve that very large growing need.”

Warby Parker launched in February 2010, when the four co-founders were still full-time students. They tapped into their savings — $30,000 from each, for a total of $120,000 — and Blumenthal used connections with eyewear manufacturers from his previous job at VisionSpring to create the company’s first inventory.

“We did pour our life savings in to get the business off the ground,” says Gilboa. Bootstrapping the business meant running it out of Blumenthal’s apartment instead of an office, and not taking any salaries.

They hired a fashion publicist to raise awareness. Vogue and GQ wrote about its launch, with GQ referring to it as “the Netflix of eyewear.” The articles published just as Warby Parker’s website went online, and the business was quickly overrun with orders. The fledgling company hit its first-year sales targets within three weeks.

Customers kept asking to visit Warby Parker’s offices to try on glasses in-person. So, after graduating and establishing headquarters in New York, the co-founders converted some of their office space into a showroom. “Suddenly, we were on track to do $3 million of [annual] sales out of our office,” says Blumenthal, calling it a “light bulb moment.”

Warby Parker opened its first brick-and-mortar store in Manhattan’s SoHo neighborhood in 2013. Last year, retail stores accounted for more than two-thirds of Warby Parker’s revenue, over $440 million. The co-CEOs hope to eventually operate more than 900 locations.

“This year, we’ll open 40 stores, and we can plan to continue on that cadence for years to come,” Blumenthal says.

Warby Parker’s revenue has consistently grown each year, yet the 14-year-old company remains unprofitable. Blumenthal and Gilboa point to an adjusted EBITDA figure — in Warby Parker’s case, “adjusted EBITDA” means excluding a series of non-recurring costs, charitable donations and tax-related expenses from the company’s bottom line — of $52.4 million last year as proof of financial viability.

That’s actually a fair assessment, says Anthony Chukumba, managing director and analyst at Loop Capital, an investment bank and advisory firm. “The company has no debt whatsoever, and generates free cash flow so they can fund continued growth,” he says, adding: “Warby Parker will be solidly profitable, from a net income perspective, by next year.”

Blumenthal and Gilboa tout plans to make Warby Parker a “holistic vision-care company” by turning stores into a “one-stop shop” for customers’ eye care needs, says Blumenthal. On a recent earnings call, Blumenthal noted that adding eye exams to retail stores helped increase Warby Parker’s average revenue per customer by more than 9% last year.

Active customers are up, too: The company had more than 2.3 million of them in 2023, a rise of 30% since 2019, according to a Make It analysis of SEC filings.

But in comparison to the industry’s giants, Warby Parker remains small. EssilorLuxottica, the Italian-French eyewear company behind Ray-Bans and Oakley, brought in more than $28 billion in sales last year. Blumenthal insists there’s plenty of space for growth within that massive global eyewear market, which is why he doesn’t hesitate to name the company’s next ambitious goal.

“We want Warby Parker to be one of the most beloved brands in the world,” he says.

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In September, GOBankingRates ranked the best retirement towns in the U.S. for the middle class in 2024.

To qualify for this study, a city had to have a population of at least 10,000 residents, with at least 25% of the population aged 65 and over.

The following factors were then considered for each city:

• Total population
• Population aged 65 and over
• Total households
• Median household income
• Number of households receiving Social Security benefits
• Number of households receiving retirement income
• Average Social Security benefits for households receiving them
• Average retirement income for households receiving it

The data sources used for the report include the U.S. Census American Community Survey, Zillow’s Home Value Index and more.

GOBankingRates’ study found that middle-class Americans will have the most success retiring in Florida, Ohio, and Arizona. Five cities in the Sunshine State alone are in the top 10.

“Florida is long established as a destination for retirees. The middle class has always flocked to Florida because of its affordability,” Ray Marek, GOBankingRates’ media outreach manager, tells CNBC Make It.

Marek added that despite the rising cost of living in Florida, the data shows that Florida is still a top destination for middle-class retirees who want to live in a place that offers a balance between affordability and quality of life.

The Villages is located in central Florida and is northwest of Orlando.

GOBankingRates’ study found that the annual cost of living in The Villages is $48,808 and the household median income is $73,415.

The Villages had the largest percentage of residents with Social Security benefits, according to GoBankingRates. The average Social Security benefit is $30,704 — one of the highest study-wide.

The Florida town also had a high livability score of 70 out of 100, Marek added.

According to U.S. Census data, The Villages is one of the nation’s fastest-growing metros. The population grew by 4.7% from July 1, 2022, to July 1, 2023.

The average value for a single-family home in The Villages is $408,342, according to Zillow.

1. The Villages, Fla.
2. Green Valley City, Ariz.
3. Sun City West, Ariz.
4. Hot Springs Village, Ark.
5. Venice, Fla.
6. Sun City, Ariz.
7. Sun City Center, Fla.
8. Punta Gorda, Fla.
9. Mesquite, Nev.
10. Englewood, Fla.

Green Valley City, Arizona, is the second-best retirement town for America’s middle class.

The Arizona town had 85% of households receiving Social Security income, the third highest in the study. The average social security benefit received by those in Green Valley City is $27,102.

The study found the annual cost of living in Green Valley City is $41,989, while the household median income is $57,785.

Green Valley City is 20 miles south of Tucson and is home to dozens of retirement communities. A bonus for retirees looking to live out their golden years in the state: Arizona doesn’t apply state income tax on social security benefits.

The area has many golf courses, including several public ones. It is also home to Green Valley’s Community Performance & Art Center, which hosts dozens of concerts annually.

Want to master your money this fall? Sign up for CNBC’s new online course. We’ll teach you practical strategies to hack your budget, reduce your debt, and grow your wealth. Start today to feel more confident and successful. Use code EARLYBIRD for an introductory discount of 30% off, now extended through September 30, 2024, for the back-to-school season.

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