HE TOLD me he cooked the best Italian food he'd ever eaten.

When he handed me the grocery list for linguine and clam sauce, he promised the dish would be elegant, easy to make and delicious. "I'll bet you've never tasted any as good," Peter Sartourius said while popping open a beer.

The list included the usual main ingredients: clams, pasta, good Italian bread and parmesan cheese. But with them Sartorius created what I was sure would be a gastronomic monster, as he poured in massive quantities of spices to make a sauce which I was certain would demolish my tender, sweet baby clams.

He dumped olive oil, Greek oregano, basil, worcestershire, 10 cloves of garlic, a small mountain of onions, wine and 2 sticks of butter into a heavy frying pan to make his sauce. When he slipped in the second stick of butter I thought I was watching the $30 worth of ingredients go up in smoke.

Thirty minutes later he brought to the table steamy, delicious linguine and clam sauce, garlic bread and a crisp green salad. It did small wonderful. Emphatic to the end, Sartorius instructed us to carefully scoop the pasta between two forks and gently work in the sauce until it clung to the pasta as if they were born together.

The meal was wonderful. Sartorius was the success he knew he would be.

In trying to reproduce the recipe I learned a lesson in economics. There are two ways to make this dish -- expensively or more expensively. If you're willing to shop around, it can cost significantly less for the same high-quality ingredients than if you were to shop at the easiest or closest two markets, as I did. The dinner cost approximately $30 for four people (plus the wines to accompany the food and the spices on my shelf). The clams were from Cannon's for $3.80 a dozen. The linguine came fresh from Pasta Inc. for $2.69 a pound, and the parmesan, also from Pasta Inc. for $2.69 a pound, and the parmesan, also from Pasta Inc., cost $3.50 for a 3-ounce container. The fresh Italian bread, a must, cost $1.20. The fresh produce, ice cream and frozen raspberries totaled approximately $7.

To reduce your bill by a third, however, you can make a trip to Morgan Seafood, 1100 Maine Ave. (the Wharf) and purchase your clams for $1.50 a dozen. The linguine you can purchase from Vace, 3510 Connecticut Ave. NW, for $1.35; Italian bread at Vace is 85 cents. The imported parmesan you can get at Old World Market, 3301 New Mexico Ave. NW, for approximately $2.90 for 3 ounces. Total bill: just under $20.

THE MENU: Linguine with clam sauce, tossed green salad, garlic bread, strawberry ice cream with raspberry puree

HAVE ON HAND: Olive oil, butter, oregano, basil, worcestershire, inexpensive dry white wine, salt and pepper, vinegar, cognac.

YOU WILL NEED: 4 dozen fresh clams, 3 heads fresh garlic, 2 medium white onions, 1 pound mushrooms, fresh parsley, freshly grated parmesan, 1 pound fresh parsley, freshly grated parmesan, 1 pound fresh or frozen pasta, romaine lettuce, radishes, your favorite non-vinegar salad dressing (non-vinegar if you plan to have wine with the meal), 1 loaf crusty Italian bread, 1 quart strawberry ice cream and 1 package frozen raspberries.

ORDER OF PREPARATION: Wash clams. Wash salad greens, radishes and mushrooms. Use 1/4 pound mushrooms, radishes and greens and made salad. Chop spices and vegtables for linguine. Steam clams.Prepare linguine sauce. Boil water for pasta. Puree raspberries. Cook pasta. Prepare garlic bread. LINGUINE AND CLAM SAUCE (4 servings) 4 dozen clams, fresh, in shell 1/2 cup olive oil 8 to 10 cloves garlic, chopped 2 sticks butter 3/4 cup clam juice reserved from steaming clams (bottled clam juice may be substituted) 3/4 pound mushrooms, sliced 4 tablespoons oregano* 2 tablespoons basil* 5 sprigs parsley, chopped Salt, pepper to taste 4 tablespoons worcestershire 1 cup dry white wine 1 pound fresh or frozen pasta Freshly grated parmesan for table

Rinse clams in four changes of cold water to remove sand. While the clams are soaking, heat oil in a heavy frying pan. Add garlic and onions. When they begin to brown, add butter.

In a large pot steam clams with enough water to cover the bottom of the pot. As soon as clams begin to open, which should take about 10 minutes, remove from heat. In a second large saucepan, bring to boil 4 quarts water for pasta. Remove clams from steaming pot, set aside on a serving platter and reserve 3/4 cup juice.

In the frying pan add clam juice, mushrooms, spices, worchestershire and wine. Return to boil and reduce by 1/3 (this takes about 10 minutes).

Meanwhile, add pasta and 1 tablespoon salt to boiling water and cook about 2 minutes, until pasta is barely tender. Drain and put in serving bowl. Add sauce to pasta and blend with 2 forks until noodles are well-coated with sauce. Serve hot with clams, still in shells, on the side. Put freshly grated parmesan cheese on table for garnish.

*Note: One taster found the quantity of herbs made the sauce gritty. The herbs can be reduced without changing too much of the flavor; use as little as 2 tablespoons oregano and 1 tablespoon basil. GARLIC BREAD Large loaf crusty Italian bread Good quality olive oil 4 cloves garlic, peeled

Turn oven to broil. Cut bread in half and lace both halves with olive oil. Put under the broiler and toast slowly, just until brown. Remove to counter and rub each half with 2 cloves garlic. Garlic will "melt" onto the bread. Lace with oil a second time and return to broiler to reheat. Serve immediately. STRAWBRETTY ICE CREAM WITH RASPBERRY SAUCE (4 servings) 1 package frozen raspberries 1 teaspoon cognac (optional, but very good) 1 quart strawberry ice cream

Strain raspberries through wire strainer. Add cognac. Pour over ice cream and serve immediately.