In 2016, Mr. DeJesus and his wife, Elizabeth, manager of the pediatric rehabilitation department at the Hospital for Special Surgery, went in with his in-laws on a three-family home in the Bronx that they purchased for $458,000. His mother-in-law and father-in-law live on the second floor. Mr. DeJesus and his wife and their daughter, Kaleigh, 13, and son, Jax, 6, take the third floor. The first floor is used as a common family area, which leads to the backyard. His mother-in-law helps with the pop-up dinners, curating everything from the glassware to the art that hangs on the walls.

The setup for Breaking Bread is intimate and homey. “This is not a restaurant. This is an evening-long celebration of food at a secret location,” according to the website.

“I have a picnic table in the dining area. I built out a center island between the living room and kitchen. Six guests sit at table and two guests are in front of me. The whole experience happens right in front of you. I’m using a home stove and oven. People are amazed — how is this guy creating this food with just that?”

From pork belly to roasted and marinated beets, Mr. DeJesus is interested in educating his Bronx neighbors on foods they might have been otherwise reluctant to eat.

“A friend told me to move to Indiana and take over out there. He’s right but he’s also wrong. Why can’t I do it in my own part of the Bronx? The food is really lacking up here,” he said. “Part of my movement is to bring people from the city and Brooklyn, to have them walk through the streets and see the Bronx is a beautiful place.”

These types of pop-up dinners are a relatively new development and represent a gray area in terms of city health department rules and licensing, according to Michael Lanza, an assistant press secretary in the city’s Department of Health and Mental Hygiene. “Food service establishments must operate out of a commercial kitchen and be inspected by the Health Department,” he said. “We do not recommend anyone set up a stand and start selling food without a license.”