Place the slices of bread on a cookie sheet, and spread ketchup or spaghetti sauce over them. Add the toppings of your choice and sprinkle mozzarella cheese over them. Pop them under the broiler for 4 or 5 minutes (until cheese bubbles and turns slightly brown. Enjoy. I usually add Italian seasonings to the sauce/ketchup. They can also be done in a toaster oven. Great way to use up any stale bread you may have, or you can use fresh.