Sans actually turns out to be capable of taking notes quite quickly - it helps to have a shorthand (or at least it's a shorthand from his perspective). And he turns out to have enough of a basic grasp of cooking to know why to do what without asking too many questions. Not to mention enough of a laid-back attitude under normal circumstances that "fill the pot until you think there's enough", or similar instructions, actually translate pretty well to him. Sans is too lazy for measurements, as a rule, unless proper science is involved. But he also has a trustworthy gut, metaphorically speaking, and so is comfortable making judgement calls.

Mostly, his questions involve what some of the vegetables on the table are called. Not everything a human might be familiar with could grow in the Underground, not even with the background magic. He asks how to tell if something's gone bad or rotten. It might be not an issue, here, seeing what he's starting to see of the castle and it's resets. But it's best to be sure, with this. With them. He asks for Lucas' opinion on how they might best go together, for future reference.

And he seems happier having this conversation, too. It brings up good memories, of a time before things went wrong. It sets before him a way to do something here and now and real for the people he cares about. It's hard to feel helpless, when soup is bubbling away.

"...spinach." Sans rattles the pencil thoughtfully against his skull, staring down thoughtfully at two pages of scrawled notes. "spinach is good for skeletons. i mean, i hate spinach. so much." He shudders in theatrical revulsion. "but it's good for skeletons."