When you go to say "Chicken Sandwich", and accidentily replace sandwich with another word, in this case situation.
Customer: I would like a Chicken Situation, Please.
Waiter: What the god damn fucking shit is a Chicken Situation?
Customer: It's like when you got bread, and chicken, and a penis, and it's all put together. Minus the penis.
Waiter: Oh, you mean a Chicken Sandwich.