Why do cookies in the oven smell good?!

Best Answer - Chosen by Voters

The heat at the outside of the cookie causes the batter to seal in a way that makes the inside sealed off from the outside, thus the steam of the inside pushes to the outside of the cookie.

Happens with bread too, it is why crusts are formed, and why the outside of break turns darker than the inside.

Called the Maillard reaction.

Anyways, in the maillard reaction, aromatic compounds are released from the crust in an exothermic reaction.

Hence the yummy smells of freshly baked cookies, breads, brownies, and cakes.

Thank the Maillard reaction. Oh, by the way, the same reaction is what causes breads and cakes to rise. The steam expands but cannot leave the inside of the bread...