What is the French culinary term given to a burnt onion used to flavor stocks and sauces?

The French culinary term for a burnt onion used to flavor stocks and sauces is indeed "onion brûlée." This technique involves charring the onion, typically by placing it directly on a flame or under a broiler until the outside is thoroughly blackened. The resulting burnt flavor adds a deep, rich note to stocks and sauces, enhancing their overall taste profile. The process allows for the development of complex flavors that are particularly sought after in classic French cuisine.

In contrast, poulet brulé refers to charred chicken, while oignon caramélisé means caramelized onion, which is a different process that involves cooking onions slowly to develop their natural sugars without burning them. Sauce brune, on the other hand, is a brown sauce in French cuisine made from a roux and brown stock, not specifically related to burnt onions. These different terms highlight the specific techniques and outcomes in the culinary world, underscoring the unique role that onion brûlée plays in flavor development.