“Right away, what you’ll notice is the authenticity of the fresh tortilla,” Mr. Fernandez boasted. “This is what it’s all about.”

The chef, who began cooking in high school, said he called on years of experience working under some of the best to launch Barcelona Bites. He has cooked for Alfred Portale at Gotham Bar & Grill in the West Village and for Daniel Bouloud at the restaurant Daniel, among others.

Mr. Fernandez still serves thousands per week at La Marina NYC, which is only open during the summer. The Upper Manhattan spot draws athletes and entertainers like Jay-Z and Beyoncé, the chef said.

Notwithstanding his glamorous clientele and appearances on the Food Network’s “Chopped” and “Beat Bobby Flay,” Mr. Fernandez struck a humble note throughout an interview early one recent weeknight as staff prepared the bar and set tables inside the sleek restaurant.

“This is something I teach my cooks now,” he said. “If you want to become a great chef, you work for great chefs because that’s how you’re going to get the signature of each one and you create your own style after that.”

Innovative creations on Barcelona Bites’ menu include three varieties of mac and cheese, with truffles, chorizo or lobster ($13-$18).

“We have three different dishes, but just three amazing profile flavors,” Mr. Fernandez said.

A self-described “texture chef,” he said he tried to include at least one crispy element in everything on the menu, which ranges from calamari to crème brûlée, with entrees like seafood paella ($30) and a tequila and lime salmon ($25) in between.

He described the tostone sliders as a multifaceted experience, from the crunchiness of fried plantains on the bottom to moist fried salami and cheese on top.

“If you’re not putting a different sauce, a layering of flavor, a seasoning here, a crispy component, your palate is going to be blind after a while,” Mr. Fernandez explained.

As part of the fun atmosphere Mr. Fernandez is trying to create, Sundays feature funnel cake ($10).

“When I think about funnel cake, I’m like, why do you have to wait till you get to a fair to have funnel cake? It’s one of my favorite things,” he said.