Pretty sure it was just a minor part:
If I recall correctly, the main character (male) ends up hiring a store clerk to cook a big family dinner (maybe thanksgiving or christmas). The would-be-chef is nervous so he adds cannabis to the meal… maybe in gravy?
The meal turns out great BUT everyone winds up high too (including grandma?).
Either I can’t remember the movie, or I can’t place it in a movie I know, but it is driving me crazy!!!