What do you do with the half-finished can of water chestnuts, the stray morsel of fish, or that quarter-head of cabbage left from the day before? Make a salad, a casserole, or a salad. Willand reveals little that we don't know (that anything can go into a concoction) and a lot we'd rather not: her quiche lorraine is made with an egg, condensed milk, and a ""can of French-fried onions""--all to use up a piece of cheese! Her leftover pork winds up in ""Short-cut Cassoulet"" with canned pork-and-beans, canned limas, and a can of tomato paste. For the moment we'd feel happier with a sandwich.