In the tea? I just stuck a leaf in a cup with water and microwaved it for a minute or two.

In food? I usually put it in as soon as I start the simmer on a liquid part of the dish. It takes a long while for the flavor to really become significant.

I wasn’t sure myself, so i made a “tea” out of bay leaves to check, and i can confirm that they do in fact have a pretty distinct flavor.