In Ratatouille, Gusteau's is the famous Paris restaurant where Remy eventually becomes a chef. The restaurant is named after the celebrated chef Auguste Gusteau, Remy's human idol and the author of the motto “Anyone can cook.”
Remy, a young rat with an unusually strong sense of taste and smell, reaches the restaurant after becoming separated from his colony. He secretly guides the garbage boy Alfredo Linguini by pulling his hair beneath a chef's hat, allowing the two to prepare food together while hiding Remy's presence from the staff.
Gusteau's is initially run by Skinner, Gusteau's former sous-chef, and its reputation has declined after Gusteau's death. Remy's cooking eventually impresses the feared critic Anton Ego, whose positive review leads to the restaurant's closure under its original management after its rat infestation is exposed. Linguini and Colette then open a smaller restaurant called La Ratatouille, where Remy continues cooking. “Gusteau's” is therefore the canonical answer for the restaurant in the film's main story.