I use this stock in place of water for adding a umami-rich Parmesan flavor to so many dishes, especially white beans, risotto, tomato soup, and rice. It can be made with fresh Parmigiano-Reggiano, but that would be a waste of expensive cheese. Start saving the end pieces that get grated to death and then thrown away. Tightly wrap them in plastic and save in the freezer until you have 8 ounces of rinds (or make friends with your local cheesemonger).