This 'Shark Tank'-backed restaurant only serves avocado dishes — and it's so busy it uses 3,000 pounds a month

Why people are flocking to this avocado-only restaurant, valued at $2 million on Shark Tank
Why people are flocking to this avocado-only restaurant, valued at $2 million on Shark Tank

With $70,000 in seed money and a little ingenuity, three 30-something Italians found a way to cash in on one of American millennials' most iconic habits: paying big money for avocado toast.

Francesco Brachetti, 30; Alessandro Biggi, 30; and Alberto Gramini, 32, opened Avocaderia, a 500-square-foot eatery with a menu entirely comprised of dishes featuring Mexican Hass avocados, in a Brooklyn, New York, food hall in April 2017.

Selling dishes like $11.45 AvoBrunch Toast with avocado and a poached egg, the shop was profitable within its first year, recouping the initial investment the co-founders had sourced from family, friends and their own savings.

There are so many people willing to eat all things avocado, in fact, that Avocaderia is expanding, with a second location serving avocado-only meals in Manhattan's Chelsea neighborhood that opened Thursday.

Avocaderia's Chelsea location on Thursday, May 17 2018.

The restaurant opened at 11 a.m. and by 1:00 p.m., the place was packed.

"Since day one, [interest] just kept growing, and we just kept adapting to demand," Brachetti, who says he spends 12 to 14 hours a day, seven days a week at the restaurant, tells CNBC Make It.

Avocaderia's CEO Francesco Brachetti

The business now has a $2 million valuation, thanks ABC's "Shark Tank." Biggi appeared on the show and landed a $400,000 joint investment from Mark Cuban and Barbara Corcoran, who agreed to take a combined 20 percent stake in the company.

All for a restaurant that only serves one trendy food?

Avocaderia's AvoBrunch Toast

On a typical day at Avocaderia's Brooklyn location, the store uses 100 pounds of avocados, Brachetti says. That's 3,000 pounds a month. In the month before taping "Shark Tank," Avocaderia did $75,000 in sales, Biggi says on the show.

When CNBC Make It visited the Brooklyn restaurant late on a Friday afternoon, customers streamed in and out, snapping photographs of the store's social-media-friendly neon sign and ordering vibrantly colored, Instagram-ready dishes like a burrata and avocado toast with green peas and mint to eat at the food hall's communal tables.

At lunch time, the line snakes into the hall.

Courtesy of Francesco Brachetti

Avocaderia's popularity even prompted a woman to fly to New York from Australia to taste the dishes, Brachetti says. She landed at JFK Airport, and immediately called up the shop asking for directions.

"Okay I just landed from Sydney I need to come to Avocaderia, just tell me how to get there," Brachetti remembers her saying. "I have my luggage, I'm coming to try your avocado toast."

"She showed up with an avocado dress," he laughs. "It was unbelievable. We were so happy because with only one location in Brooklyn we were able to reach customers around the world."

A neon sign in Avocaderia

Brachetti and Biggi first met in 2006 studying finance at Bocconi University in Milan, and later attended graduate school together. Brachetti left Italy to work at an e-commerce company in Mexico, where he began eating avocados nearly every day, a staple in Mexican diets. He would mix them in morning smoothies with mango and almond milk, or with have them his lunch.

Biggi worked at an investment bank, a consulting firm and a series of start ups, moving to Seattle, Washington. He noticed American consumers' desire for healthy and filling lunch options.

Then, in 2016, avocado toast began to take off in the U.S.

That led the friends to an idea: Why not open an avocado-only restaurant?

The pair launched an Instagram account on April 10, 2016, to gauge interest for the idea, posting pictures of potential dishes from their respective cities in two different countries. They had their eyes on New York, which is the city most interested in avocado toast according to Google Trends.

"The first thing we did when talking about Avocaderia was to open an Instagram account," Brachetti explains, "to see how people were reacting to our food proposal, to see if there was a market for an avocado-only restaurant.

"We were using a lot of New York related hashtags to see if people were willing to come and try our food," he says.

"We always say we were born on Instagram."

To take the best photos of avocado dishes, Brachetti arranged "a little studio" in the kitchen of his apartment in Mexico. When visiting Biggi in Seattle, the duo "used to go on top of his building to take videos," like one where toppings are placed onto toast.

Within a few days, the account had almost 500 followers. Soon, it grew to 10,000. News organizations in South Africa and New Zealand even started to write about Avocaderia as if it were open, although at that time it only existed on social media.

"The response of the public was so overwhelming we knew we were onto something good," Brachetti says.

Brachetti quit his job and lived off of his personal savings while developing the idea and scouting for locations in New York.

"I felt that I had to make a choice between my full-time job and Avocaderia because it was not possible for me to keep dedicating half of my time to both projects," he explains. "I decided to quit, and took a leap of faith."

Brachetti and Biggi needed a chef, so Brachetti reached out to his cousin Alberto Gramini, who runs a catering and events business in Italy, to design the menu. Among the three's family and friends, they raised the money to open the Brooklyn shop.

It was "pretty much self-funded," Brachetti says, until "Shark Tank."

At the original Brooklyn location's opening on April 10, 2017 — exactly a year after the Instagram account launched — it seemed the risk was well worth it.

"We had a line of around 55 customers outside the door," Brachetti remembers.

"As soon as we opened the door everyone ran in and started ordering food," he says. "We ran out of avocado in two hours."

The unexpected crowds made the store's first week so hectic Brachetti accidentally sliced his hand open while halving an avocado.

"We had all these customers coming in, we only had a couple of employees and we were just trying to do all of the different things in the kitchen," he says. "I was cutting avocados like crazy and I cut my left hand.

"From that day on I learned how to cut avocados."

Next, the founders hope to use the cash and real estate savvy of "Shark Tank's" Mark Cuban and Barbara Corcoran to expand across the U.S., with plans to open 20 restaurants in the next four years, targeting Los Angeles and San Diego first.

Even Brachetti is shocked by Avocaderia's success: "It's pretty unbelievable."

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Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."