If I say "straight" instead of "flat", would it change the general nuance of the sentence?

Rebecca

Yes, it would change the nuance of the sentence, and it sounds very odd in English. We do not typically use "straight" when cooking, especially when rolling out dough. We use "flatten," "shape," "roll," or "knead" for dough. Ex: Now, knead the dough for 5 minutes. Ex: Roll out the dough until it's nice and flat.