Adan Trinidad, 39, a chef and a key part of the ebullient spirit that defines Philadelphia’s three Pistola’s bar-restaurants, died Tuesday, Oct. 5, apparently after he fell on the street near his South Philadelphia home, his fiancée said. The city Medical Examiner’s Office said the cause of death was not yet determined, pending investigation.

“His motto was ‘Live every day to the fullest,’” said Katie McCann, who was by his side for 6½ years after they were introduced by a mutual friend. “He had a heart of gold.” She said Mr. Trinidad “loved food, his friends and family, and Simone,” his pitbull-terrier mix, whom he referred to as “my princess.”

Casey Parker, who with Joe Gunn founded Jose Pistola’s, a Tex-Mex-theme bar-restaurant in Center City Philadelphia, met Mr. Trinidad nearly 15 years ago, while Parker was tending bar at Fergie’s Pub and Mr. Trinidad was a sous chef at the nearby El Vez.

“We didn’t really hit it off then,” Parker said, “but I got to know him through the years and had heard how talented he was as a chef.” When Parker and Gunn began to expand their restaurant holdings in 2012, Parker called Mr. Trinidad.

“He ended up interviewing me,” Parker said, adding that Mr. Trinidad would sign on only if he had control in the kitchen. “He just had a great style, a knack for interesting, different flavors. The first thing I ever had of his was spicy tuna guacamole. He said, ‘Here, try this.’ I said, ‘This is going to be awful.’ It was the greatest thing I ever tried.”

The three men went on to open Sancho Pistola’s (2014) in Fishtown and Pistola’s Del Sur (2017) in South Philadelphia. “He understood how to make people move in the kitchen to get the best out of everybody,” Parker said. “People loved working for him, even though it wasn’t easy — but not in a bad way. He was a teacher. He trained a lot of incredible people for us.”

Mr. Trinidad, born in Puebla, Mexico, immigrated to the United States at age 12. His first restaurant job, as he told the newspaper Al Día in 2019, was washing dishes at La Campagne in Cherry Hill, though he was quickly promoted to line chef. His next job was line cook at the Capital Grille in Philadelphia. After he “got sick of smelling like steak,” as he told Al Día, he joined Stephen Starr’s El Vez in 2004 as Jose Garces’ sous chef.

After a stint at Starr’s Alma de Cuba, Mr.Trinidad returned to El Vez as the head chef but then left to work in New York. He returned to Philadelphia just before he started at Jose Pistola’s.

Garces, who also later moved on from El Vez, called Mr. Trinidad’s death a “tragedy. Philly’s culinary scene lost a light this week.” Garces said that although Mr. Trinidad was “naturally gifted,” he was “also a great example of hard work and dedication. He brought a lot of laughter to the line, while also maintaining a high standard of quality, both in his personal and professional life.”

Kris Serviss, a chef who met Mr. Trinidad in 2014 when both praised the other’s tacos on Twitter, called him a connector. “I had so many great conversations with people [Tuesday]. I don’t know if I would have met them if not for my relationship with Adan,” he said.

Besides his fiancée, his survivors include his father, Adan Trinidad; his mother, Lidia Mendez; his son, Antonio Trinidad; his daughter, Leslie Trinidad; a brother, Carlos Trinidad; and a sister, Maribel Trinidad.

There will be a viewing at 10 a.m. Wednesday, Oct. 13, at Sacred Heart of Jesus Church, 1412 S. Third St., Philadelphia. A Mass will follow at noon at the church. There will be a reception after the Mass at Pistola’s del Sur, 1934 E. Passyunk Ave., Philadelphia.