One of the my favorite TV momemts would have to be that Seinfeld episode ("The Fatigues") where Frank Costanza cooks for the first time since the Korean war.
New scene.
Frank and Estelle are in their kitchen.
Estelle: Here's your omelet.
Frank: It's dry.
Estelle: That's the way I always make it.
Frank: Well it sucks.
Estelle: What did you say?
Frank: Your meatloaf is mushy, your salmon croquettes are oily and your
eggplant parmesan is a disgrace to this house!
Estelle: Well that's too bad, because I'm the only one who cooks around here!
Frank: Not any more! Gimme that spatula! I'm back, baby!
Moviewise, I like the end of Mostly Martha where she critiques her psychiatrist's cake since she does not believe that he made her exact recipe. That movie's been mentioned on here before as a good foodie film.
Also, another good scene in Lord of the Rings TTT (might have been in the extended edition only) was where Sam disgusts Gollum by making rabbit stew from a nice fresh kill that Gollum would prefer raw. Sam then tries to explain to Gollum what potatoes are, and finally gives up. "Poe-tay-toes!"