Why do some foods taste better the next day? Many people think that certain foods, like lasagna, many stews and hearty soups, tomato sauce and so forth taste better the next day. My question is, is that really true, and if so, why? The conventional answer is essentially, "the flavors marry", but that doesn't mean much. I asked this question on Dave Arnold's Cooking Issues podcast and he had some interesting answers but I'm curious to see what else this community will come up with.
For pastas at least, the noodles have a chance to absorb more flavor directly into the bland noodles. Same with potatoes in stews.

If the dish cools and is then reheated, more water is lost into the air. This effectively reduces the dish and intensifies flavors.