As you stand with slumped shoulders and glazed eyes contemplating a trip to the trash can with the turkey carcass, consider this: Americans throw out $11-billion worth of food each year, according to a report of the General Accounting Office. Right into the garbage, starving children in China notwithstanding.

That's a lot of leftovers. And the toll gets bigger when you consider the energy dollars spent in raising, transporting and storing the food before it gets thrown away.

Anticipate waste to avoid it:

* Waste often occurs on the way home from the supermarket. Watch that your eggs and bread aren't packed on the bottom of the bag.

* Watch how you prepare foods. Some people think that throwing away potato peels is as natural as throwing away cellophane bags. Some, however, like the chewiness and added fiber that potato skins lend their beef stews, french fries and potato salads.

* According to the GAO study, families that know about food safety throw away less food. Presumably they know what should and should not thaw on the counter.

* Plate waste and the waste of overpreparation account for a large part of food thrown out in this country. Jean Mayer, nutritionist and president of Tufts University, noted at a recent Washington luncheon that Americans are inclined to overload their plates. When the meal is over, the plates are scraped to avoid the onus of leftovers.

Well, leftovers don't need to taste bad. Indeed, there are many foods that improve on sitting, among them casseroles in which leftover turkey can play a part. Combine leftover turkey, dressing and gravy and bake this hash while you simmer the bones of the turkey with onion, celery and herbs to use as a base for soups, sauces, rice, beans or bulgur.

Or use leftover turkey meat instead of ground beef in your favorite taco and lasagna recipes. Grind it for croquettes to freeze now and eat (with a cream sauce fortified with mushrooms) in March when you aren't tired of turkey. Throw it into quiche, wrap it into crepes, mince it into omelets. Chop it well and combine it with bread crumbs, saute'ed onions and a light cheese sauce to stuff zucchini boats.

The following dish, adapted from a recipe in "The Vegetarian Epicure," by Anna Thomas, leaves Thanksgiving far behind. Dressing, sage, gravy, cranberries and other familiar accoutrements of the holiday are forgotten for this sweet-and-sour dish which can be thrown together after one quick trip through the express lane of the supermarket, provided you already have flour, sugar, salt, pepper and butter and/or oil already on the kitchen shelf.

We've even allowed the meat as one of the ingredients. If you've got leftover turkey at home and have room for one more item, buy apples to bake with butter and brown sugar (350 degrees in a covered baking pan) for dessert. If you're inclined, make broth with the turkey bones and use that for cooking the rice.

EXPRESS LANE LIST: turkey, green peppers, onion, dijon mustard, worcestershire sauce, red wine, (brown) rice or wheat toast, brussels sprouts. SPIRITED TURKEY (2 to 3 servings) 2 medium bell peppers 1 onion 1/4 cup butter 2 cups turkey pieces 2 tablespoons dijon mustard 1/4 cup brown sugar

2 tablespoons worcestershire sauce 3/4 cup red table wine Salt and freshly ground pepper Hot rice or toast

Wash, core and seed the green peppers. Chop them. Peel onion and chop it. Melt butter in skillet. Add peppers and onion and cook until the onion is transluscent. Add turkey pieces and keep over low heat. Combine mustard, sugar and worcestershire sauce to form a paste. Add wine and season with lots of pepper and a little salt. Add the sauce to the skillet and cook for 30 to 45 minutes, until the sauce is reduced and thickened. Serve over brown rice or toast. BRUSSELS SPROUTS (2 servings) 1/2 pound brussels sprouts 2 to 4 tablespoons butter Salt and freshly ground pepper to taste

Place a steamer basket in a large saucepan. Fill the pan with 1 to 2 inches of water (so that water does not rise above steamer basket). Using a paring knife, make cross-hatches in the bases of the brussels sprouts. When water comes to a boil, place sprouts in steamer basket and cover the pan. Cook 5 to 10 minutes and drain, discarding water. Melt butter in same saucepan and return cooked sprouts to it. Salt and pepper to taste. Turn them quickly over medium flame to heat through and coat with butter. Serve at once.