He Began With Sauce. Here’s Why This Brisket Sandwich Goes for $13.50.

Who has not dreamed of turning a side hustle into a full-time gig? Luis Rivera Jr., who sells barbecue on the weekends in the Bronx from his food truck, is trying.

The thing is, Mr. Rivera never had any intention of selling meat.

A New York City native and barbecue aficionado, he became obsessed with a piquant sauce he tasted in 2009 at a Mets game. He set out to recreate it at home, a quest that led him to quit a secure job as an executive chef and enter culinary school.

By 2019, he was marketing his own sauces, which evoke flavors of traditional Puerto Rican cooking. He used the Father & Son’s moniker, with a label featuring a snapshot of him and his son stirring a pot.

Then the pandemic and an injury kept him home. Mr. Rivera trawled online for insights.

In 2021, he started selling his sauces on the weekends at the Gun Hill Brewery in the Allerton neighborhood of the Bronx until it closed last month. A friend brought a smoker for meat to make it easier for customers to taste sauce samples. Food ran out in three hours, he said.

“The food outshone the sauce,” he said. “The breadwinner was the food.”