Cut bread into 1/2-in. slices, leaving slices attached at the bottom. In a small bowl, combine the butter, mustard, parsley, garlic and red pepper flakes. Spread on every other slice. Place tomatoes, mozzarella, salami and pepper rings between the buttered slices. Wrap in foil. Bake at 350° for 10-12 minutes or until cheese is melted.