Burgundy-Style Red Wine Sauce

This sauce is served in Burgundy with poached eggs (a delightful brunch item, by the way), but it can also be used for chicken, meat, or fish. Its greatest advantage is that it requires no broth—just a piece of prosciutto end, which some grocers will give you or at least sell for far less than the typical cost of sliced prosciutto. It is traditionally thickened with a little flour