With the price of quality Italian Parmigiano Reggiano cheese, making use of every precious bit makes sense!
Save the heels and ends of your cheese in a zipper bag in the freezer until you have about a pound of rinds. Cook them as you would veal or beef bones to make a flavorful stock that's a wonderful addition to soups, pastas and vegetable braises.
Heat the oil in a large stockpot. When it's hot, add the onions. Reduce the heat to low, place a round of parchment or wax paper directly on top of the onions, and sweat them until they're softened, about 15 minutes, stirring occasionally.
Discard the paper and add the wine to the pan. Raise the heat to high and bring to the start of a simmer. Add the remaining ingredients and bring to a boil. Reduce the heat to maintain a slow simmer, and cook the stock for 2 hours or until the liquid has reduced by about half.
Let the stock sit at room temperature until lukewarm. Strain through a fine mesh sieve and discard the solids. Refrigerate the stock until cold, then cover and freeze for up to 3 months.