Quarter the sweet peppers, then remove stems, seeds, and membranes. Place, cut side down, on a baking sheet. Bake in a 425 degree oven for 20 to 25 minutes or until skins are blistered and dark. Remove from baking sheet; immediately place in a paper bag. Close bag and let stand about 30 minutes to steam so the skin peels away more easily. With a knife, remove skin from peppers, pulling skin off in strips. Discard skin.