Emeril is most well-known for his TV show Emeril Live on the Food Network, one of its highest-rated programs. Lagasse was the first host chef of Food Network's beginners' cooking show, How to Boil Water, in 1993. After several appearances on several other FoodTV programs, he hosted his own show, The Essence of Emeril. "Essence" in the title refers to the name of a spice blend of his own concoction that he sometimes uses in his cooking. Emeril also often suggested that viewers of his show create their own spice blends that reflect their personal tastes and be unafraid to use them to customize the dishes he would teach.

Emeril is known for his light and jovial hosting style as well as several catchphrases, including "BAM!", "Kick it up a notch", "Feel the love", and "Oh yeah, babe", usually said before or after adding something spicy to a dish, or after the reaction to adding something (respectively).

Lagasse initially gained fame in the culinary world after opening his first restaurant, Emeril's Restaurant, in New Orleans, Louisiana, in 1990. It was designated "Restaurant of the Year" in Esquire magazine of that year. Emeril is mainly known for his emphasis on Creole and Cajun cooking styles. Indeed, many of his restaurants as well as his corporate office, Emeril's Homebase, are located in New Orleans. Lagasse was the chef/proprietor of nine restaurants.

Emeril has written several best-selling cookbooks, from Emeril's New New Orleans Cooking, his first book which was published in 1993, to From Emeril's Kitchen, published in 2003.

Emeril briefly starred in a self-titled TV sitcom on NBC during the fall 2001 season, but it was canceled after a few episodes and widely panned by critics. Recently he has appeared in Crest toothpaste commercials yelling his trademark catch phrase, "BAM!!!".

Emeril Lagasse also has a line of kitchen knives made by Wusthof and cookware made by All-Clad. He is also an accomplished drummer, having passed on a scholarship to New England Conservatory of Music.