Dean is always one to stuff his mouth and Castiel does feel he's better equipped to read the expressions the hunter has while chipmunk faced. "Yes," he answers, knowledgeable enough to know the recipe and measurements aren't what Dean are looking for. The thumps up are his next clue that he's done a good job which prompts a smile. "You can tell me if you need more." It's an offer as well as a cause for pride.