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The Sweet Side Hustle She Started 'On a Whim' Turned Into a $20,000-a-Month Income Stream: 'It's Simple, It's Affordable and It's Fun' It was the summer of 2015 when Katherine O'Brien, founder of Cream Cruiser and Bike Business University, decided to launch her own business.

By Amanda Breen Edited by Jessica Thomas

Key Takeaways

  • O'Brien found inspiration for her ice cream bike in the "hot, sunny days" of a Baltimore, Maryland summer.
  • She got the "business up and running for under $10,000" in just a few months and went full-time within three years.
  • Now, her online course that teaches the bike business model averages $20,000 a month.

This Side Hustle Spotlight Q&A features Katherine O'Brien, owner and founder of Cream Cruiser, a Baltimore, Maryland-based company that distributes handcrafted frozen desserts and provides full-service and drop-off catering for events. She is also the founder of Bike Business University, an online course for entrepreneurs who want to take advantage of the bike business model.

Image Credit: Elizabeth Rodenhizer Photography. Katherine O'Brien.

When did you start your side hustle, and where did you find the inspiration for it?

My side hustle journey has been two-fold. I started my ice cream business, Cream Cruiser, in May of 2015 kind of on a whim. I was working a regular 9-5 but always knew that I wanted to create something that was my own.

At the time, I was walking to my 9-5 job through the Inner Harbor of Baltimore, which, over the summer, was always filled with lots of visitors and corporate commuters such as myself. Some days, there would be so many people that you could hardly navigate through the crowds. I was constantly thinking to myself how amazing an ice cream cart would be on a hot, sunny day.

Also, at this time, the mobile food industry had really started to gain traction. I wasn't interested in starting an ice cream truck because of the investment. I wanted something smaller and simpler. After some research and phone calls, I found a small business that manufactured custom food bikes. And within minutes of speaking with them, I knew it was for me.

I got the entire business up and running for under $10,000 and launched in just a few months. I started at a local farmers market, and it wasn't long until I got into catering weddings, corporate and college events, etc.

Image Credit: Elizabeth Rodenhizer Photography

Related: She Started a Furniture-Flipping Side Hustle to Pay Off a $10,000 Dental Bill. It Surpassed Her Full-Time Job's Income Within a Year — Earning Up to $37,000 a Month.

I worked a full-time job and sold ice cream during the summer for over three years to be able to put every penny back into the business. Finally, in 2018, I quit my job to go all in on my ice cream business. At this time, I also expanded into wholesale and even private label.

The second part of my side hustle journey came into play after a tough few years from 2020-2022. As a small business in the food and beverage and events industry, I felt like I could not keep my head above water and knew that something needed to change.

As events were introduced back into our lives, my little catering business started to take off. All of a sudden, I got my fire back and had a great income stream that I had been missing over the past two years during the pandemic. Towards the end of 2022, I decided to stop focusing on the wholesale and private label and go back to doing what I loved, which was selling ice cream from a bike at events.

This led me to part two of my side hustle journey. I created Bike Business University to share my love of this ice cream bike business model with as many people as possible. It's simple, it's affordable, and it's fun! My goal is to make the bike business community just as big as the food truck community.

Related: This Ballet Dancer Needed a Side Hustle When the Pandemic Stopped Performances. So She Spun Her Unique Skill Set Into a 6-Figure Business.

What were some of the first steps you took to get your side hustle off the ground?

The first thing I did was start my Ice Cream Bike Lady social media accounts. I began sharing my journey and what I loved about my ice cream catering business. I was also using this time to learn more about digital marketing and how to teach others what I had learned over the years. I wanted to help them avoid some of the lessons I learned the hard way. Pretty quickly, I started connecting with people all over the country looking for a mentor to help them get started and, most importantly, hold them accountable for bringing their business to life. So, I continued listening to my audience and created what they were asking for.

Image Credit: Katherine O'Brien

What were some of the biggest challenges you faced while building your side hustle, and how did you navigate them?

Due to the challenges that came with the pandemic, for a while, I struggled with feeling like I had failed — that I didn't have what it took to scale my ice cream business to what I had originally envisioned when I first went full-time with it. But in reality, those challenges were the best thing that ever happened because they forced me to refocus my goals and brought Bike Business University into my life. It took me a while to be okay with the fact that change is healthy, and being an entrepreneur, it is incredibly important to adapt as needed.

Related: I Spent the Last 3 Years Building My Side Hustle Into a Full-Time Business. Here's What I Learned.

How long did it take you to see consistent monthly revenue, and at what point did the side hustle's income surpass your full-time job?

I launched Bike Business University before I had even created it. I had an idea of what the program would look like and had started developing the backend, but it was far from ready. I wanted to make sure it sold before I dove in 100%, so I did a pre-sale. Within the first week, I had sold over $10,000 in courses. I am very grateful that it did not slow down after that, and almost immediately, I replaced my full-time job's income.

You've turned your side hustle into a full-time business. How much average monthly or annual revenue does it bring in now?

Currently, I average $20,000 per month with Bike Business University. With the recent growth, I am projected to double that by the start of summer 2024.

What's your advice for other side-hustlers who hope to turn their ventures into successful businesses?

Start before you are ready, and trust yourself enough to know that if you're passionate about what you're doing, you will figure it out as you go. It's okay to make mistakes. It's okay to learn lessons the hard way. It's okay to adapt and make changes as you need to. Just keep going and keep growing.

Related: 4 Things Entrepreneurs Don't Need, According to This Outdoor Adventurer and Creative Founder

Also, learn online skills. The internet and social media can be incredibly powerful when you understand the opportunities available. Nothing brings me more joy than selling ice cream out at events, but having an online side to my business has been a total game-changer for me — and provided me with an uncapped income that would not be possible solely from ice cream sales.

Amanda Breen

Entrepreneur Staff

Senior Features Writer

Amanda Breen is a senior features writer at She is a graduate of Barnard College and received an MFA in writing at Columbia University, where she was a news fellow for the School of the Arts.

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