Opening a restaurant is not easy — and running a food truck may be an even taller task. "With food trucks, there's no road map on how to start one," Yumpling co-founder Christopher Yu tells CNBC Make It. "They are common, but, for whatever reason, there just isn't that much information out there on how to do this." Through trial and error, Yu, 28, and his co-founders, Jeffrey Fann, 35, and Howard Jeon, 34, have built a successful business with their popular food truck, Yumpling, which has been serving Taiwanese-American fare on the streets of New York City since 2017. Their flaming red truck draws a lunch crowd that lines up for dumplings, beef bowls and fried chicken sandwiches as early as 11 a.m. From 11:30 a.m., when the window opens, to 2:30 p.m. when it closes, the queue is consistently dozens of customers deep.

The Yumpling line starts forming before the window opens Source: Yumpling

"The idea started while I was at another job," says Fann. The co-founders had no prior experience in the restaurant industry before Yumpling — Fann was working as a lawyer, Yu was a recruiter and Jeon was living abroad in Vietnam running a language school — but all three had grown up surrounded by Taiwanese food. "Chris, being a native of Taiwan, had a lot of really insightful information about the culture," says Fann. "My experience was more through my family, growing up in a Taiwanese household in the United States and eating the food and being exposed to the culture that way."

With food trucks, there's no roadmap on how to start one. Christopher Yu Yumpling co-founder

In 2015, Fann was the first to quit his job. He started developing a menu and testing it by hosting pop-up dinners and selling his food at the Long Island City flea market. "It ended up being pretty successful, first in flea markets," he says, "and then we decided to take it to the next level and see if we could do a food truck." Yu and Jeon left their jobs shortly after to pursue Yumpling full-time. They bought the truck in February 2017 from Syracuse University through Autotrader, an online marketplace. "It was an old truck that Syracuse had used to deliver things internally on campus," says Fann. It was six years old, "but the mileage was very low and that's what attracted us to it." They outfitted the truck, obtained all the necessary permits and were ready to open for business in June 2017. After two successful years selling on the streets of New York, the co-founders plan to expand their menu and open a restaurant this fall in Long Island City, Queens.

Yumpling started as a stand at the Long Island City flea market Source: Yumpling

To see what it really takes to run a successful food truck in the culinary capital of America, I spent a day on the job with the Yumpling team. Here's how it went.

12:30 a.m.: Commute to Long Island City

The Yumpling crew start their day in the middle of the night. My alarm sounds around 12:15 a.m. I'm meeting Yu at 1 a.m. in Long Island City, Queens, where the truck parks by their commissary overnight. To get there on time, I quickly bundle up — it's winter in New York — and leave my apartment by 12:30 a.m. That's around the same time Yu heads out from his place, but he doesn't get any sleep beforehand — he prefers to stay up and work out until it's time to leave.

The Yumpling co-founders: Christopher Yu, Jeffrey Fann and Howard Jeon Source: Yumpling

1 a.m.: Pick up the Yumpling truck

I arrive a few minutes early, but Yu is already waiting for me in the truck. I hop in the passenger seat, and we head toward Midtown Manhattan, where Yumpling parks on Tuesdays and Thursdays. It parks near Bryant Park on Mondays, Dumbo on Wednesdays and Soho on Fridays. The streets aren't congested at this hour, and we make it to West 49th Street between Sixth and Seventh Avenues by 1:30 a.m. Driving back to the commissary in afternoon traffic will take much longer, Yu tells me. The reason we arrive so early is because location is everything. Competition is stiff, as this is a popular block for food trucks because of its proximity to so many big office buildings. The later you show up, the less likely you are to snag a parking spot. It's important for Yumpling to stick to a weekly schedule and park in the same places because it helps build and retain a customer base, says Yu: "We don't want to have to disappoint those people who have come to rely on us for their lunch." While most trucks will park between 3 and 5 a.m., the Yumpling team doesn't mind sacrificing sleep to guarantee their spot.

The truck, in Long Island City around 12:30 a.m.

We're not the only early birds — there's already another food truck parked on this specific block — but we still get a good space. Yu parallel parks the massive vehicle with help from a back-up camera. It's been a "very good investment," he tells me. Immediately after parking, he gets out and walks behind the truck to where the generator is located and turns it on. The generator powers everything, including the fridge and freezer, where most ingredients are stored.

2 to 7 a.m.: Sleep in the truck

The way the regulations are set up in New York City, Yu can't just park the truck, leave it and come back in the morning: He has to be in the vehicle at all times, so he'll camp out overnight. He can't sleep in the back of the truck where the food is prepared, so he turns the driver's seat into a makeshift bed. He makes it as comfortable as possible: "The trick is, you have to tilt the wheel so the wide side faces up," he says as he puts the key in the ignition, starts the truck to reposition the steering wheel and stuffs it with spare jackets to form a "portable pillow."

Yu and Jeon alternate parking and sleeping in the truck Source: CNBC Make It

It's about 20 degrees outside, and not much warmer in the truck (there's no heater), so Yu relies on layers. Today, he's wearing three pairs of pants and two jackets. In the summer, he deals with the other extreme: "It's tougher to sleep in the summer than the winter because the heat is just unbearable. That's just part of the process that you have to get used to." I head back to my apartment, feeling thankful for my bed and heating system, while Yu falls asleep in the truck. When he wakes up around 7 a.m., there will be four to five other food trucks parked on the block.

7 to 11:30 a.m.: Morning prep

By the time I meet back up with Yu, Yumpling's manager, Dani, has arrived and started morning prep. Two more employees show up between 9 and 10 a.m. to assist. The team pre-fries chicken, marinates and cooks beef, assembles side salads and labels containers with Yumpling stickers. Three giant rice cookers are going at once. Thirty minutes before opening, they'll start cooking the dumplings, which take up a lot of space in the small kitchen: Of the eight total stovetops, seven are reserved for dumplings.

The dumplings are the top-seller Source: Yumpling

By 11 a.m., all six employees are on the truck. This is when space starts to get tight, and I have to hop off to let them finalize preparations for service.

11:30 a.m.: The window opens

By the time Yumpling opens for service at 11:30 a.m., there's already a line of customers snaking along West 49th street. People arrive as early as 11 a.m., especially if they want one of the elusive beef bowls: Due to limited space on the truck, the team can only prepare 15 bowls a day — and they go fast. Today, they're gone within 20 minutes. The quickest they've ever sold out is five minutes. "It's a running joke that [the beef bowl] is a myth," says Fann. In the three hours they're open for service, business doesn't slow down. To maximize efficiency, each employee has a specific role on the truck: one works the fryer, one is on dumpling duty, two are on assembly, one is at the register and there's one "floater," who does a little bit of everything.

The Yumpling food truck serves lunch in Manhattan and Brooklyn starting at 11:30 a.m. Source: Yumpling

2:30 p.m.: The window closes

After three hours of service, Yumpling is sold out of every menu item: the only food left on the truck is one piece of fried chicken, three dumplings and a bit of rice. The dumplings are their top-seller: "On a good day we can go through approximately 1,200 to 1,400 dumplings," says Yu. Fann estimates they'll help 200 to 250 customers in a three-hour window, with many customers ordering multiple items.

3 p.m.: Drive back to the commissary

After a quick clean up, the full team heads back to the commissary in Long Island City to do a deep clean of the truck and replenish it with ingredients for the next day. They'll wrap up between 6 and 7 p.m. It's a long day, but "just like any job, you get used to the schedule over time," says Yu.

One of Yumplings' menu items: the fried chicken sandwich Source: Yumpling

The cost of running a food truck

The start-up costs that come with opening a food truck range from $100,000 to $150,000, depending on the type of equipment required, the quality of the buildout and the cost of the actual truck, Fann explains: "When we were looking at different trucks, some of them were as cheap as just a couple thousand dollars, but we also saw ones that were as much as $50,000 to $60,000. The cost of the truck can be a very big variable." The other big variable is the equipment that you put in the truck. The co-founders had to install everything from refrigerators and freezers to deep fryers.

Fann's wife standing in front of the original truck, which they outfitted and turned into Yumpling Source: Yumpling

They also invested in a dual window, which allows them to serve out of either side of the truck. That's particularly helpful in NYC, where, "on certain streets, you will only be able to face one side and not the other," says Yu. "Having a dual window allows you to park in more spots." "Because there's so little space, everything on a truck is a trade-off," Fann notes. "For example, our driver-side door actually doesn't open anymore. We had to decommission the door to make room for that window. It also meant that we wouldn't be able to put a cooking apparatus in that area." Yu, Fann and Jeon pulled from their own savings to launch Yumpling. "Luckily, the start-up cost, though high, is not prohibitively high, and we were lucky to be able to handle that on our own," says Fann.

The full Yumpling team Source: Yumpling

Now that the truck is up and running, they have a variety of other expenses to account for, including cooking gas, fuel for the vehicle, portable Wi-Fi to run the POS system on the truck and parking tickets, which they accumulate regularly during service. "A lot of people will say, 'Trucks are great because you don't pay rent,'" says Fann. "Well, you do in different ways, like getting parking tickets daily." Other regular costs include their parking space in Long Island City and a commissary space they rent out and use to prepare food.

A lot of people will say, 'Trucks are great because you don't pay rent.' Well, you do in different ways, like getting parking tickets daily. Jeffrey Fann Yumpling co-founder

Plus, there's the cost of maintaining the truck, says Fann: "I think everything on the truck has probably broken at least once at this point. That has everything to do with the fact that we drive across a lot of potholes — it's very bumpy — and things like deep fryers and rice cookers were not created with this use in mind."

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