Ohhhh for the love of duck. If you use my recipe on this site for Roast Duck with Apricot Glaze, you will have a lovely duck stock, as well as some decadent duck fat. I love to enrich my duck stock further with veal bones from my nearby ethnic market. This recipe is adapted from one on the Saveur web site. Although typically Parmesan cheese is used, Manchego is also very good; and since that is what I had available, that is what I used.