His interest in his grandmother’s cooking, Isabella admits, had much to do with the fact that his mom was a vegetarian while he was growing up in Little Ferry, outside Hackensack. His mother prepared a mean multi-layered eggplant Parm, the son recalls, but mostly he remembers an endless parade of hummus, tabbouleh and other health-food standards of the 1970s and ’80s. Isabella was, without question, an oddball eater for a kid. “I didn’t start eating chocolate until I started cooking,” he says. “I thought it was too sweet.”

Isabella’s decision to enter the culinary world was not exactly based on a desire to become the next Jacques Pepin. “I wanted to travel. I wanted to get a job anywhere in the world,” he says. “I knew that [cooking] was one of the outlets that would help me do that.”

He worked hard to put himself through what was then called New York Restaurant School (now the Art Institute of New York City). He worked six nights a week at a restaurant in New Brunswick, N.J., took the early-morning train to Manhattan five days a week for school and still managed, on occasion, to help his older sister, Diana, raise her young son. The siblings were, for financial reasons, living together at the time.

Those who know Isabella say that viewers grossly misunderstood the dynamic of the scene. Isabella and Carroll are friends, and Jerseyites like Isabella have developed peculiar customs for how to treat their friends. “I can understand his sarcasm and bravado,” says Blais, a Long Island native. “When you love someone, you give them a hard time sometimes.”

Misunderstood or not, Isabella’s “Top Chef” appearances established a pattern: The negative was often difficult to separate from the positive. Even as he started to change public opinion during “All-Stars,” Isabella continued to find himself in the middle of kitchen controversies.

Blais and others initially stewed over the fact that Isabella had nicked the concept for a chicken “oyster” dish from Blais’s recipe book. (Blais today: If that’s stealing, “I’m guilty of stealing a thousand things.”) Later, competitor Marcel Vigneron accused Isabella of purposely botching a monkfish dish during a team challenge to force Vigneron out of the competition. (Isabella says Vigneron is a “spoiled brat.”) And in the penultimate “All-Stars” episode, some hard-core online followers speculated that Colicchio had persuaded guest judge Wolfgang Puck to change his vote and keep Isabella around for the finale.