You can use any filling that you desire. Make sure to dry it if it's sauteed, so it's a great idea to use a paper towel to absorb any moisture. If you are using sauce, such as pizza sauce, do not go overboard. Add a tablespoon or 2, also on one-half of calzone - dough rolled disk. TIP --- If you are buying pizza dough in the can (Pillsbury) make sure to get two of those because, for 4 calzones, 1 can will not be enough unless you are going to make a smaller version. Try looking for homestyle pizza dough in a bakery section of your grocery store. Ask, if you can't find it. They make it fresh and store in those little fridges close to deli meat, cakes, and bread.