To finely slice the basil, stack the basil leaves and cut with a sharp knife into thin strips.
Bake these tasty appetizers up to 24 hours in advance. Transfer them to an ovenproof baking dish; cover and refrigerate. When ready to serve, reheat at 350° for 20 to 25 minutes.
Cremini mushrooms are the baby version of the larger portabella mushroom. They're lighter in color and have a milder flavor.