PARMIGIANO - REGGIANO!; Pasta isn't pasta without this 'pearl of Parmesan'

''SIGNOR! Parmigiano-Reggiano, Parmigiano-Reggiano!'' My kind elderly waiter, his voice trembling with concern, all but tripped over some empty chairs as he rushed to my table.

Without explanation, he snatched the glass container of grated cheese from my table and liberally sprinkled Parmigiano-Reggiano over my bowl of steaming tortellini.

Here at lunch in one of those quaint little trattoria, I had in broad daylight attempted the unthinkable. I tried to sample a few pieces of pasta au naturel, without the Italians' beloved pearl of Parmesan cheese - Parmigiano-Reggiano.

I would have added it eventually, but how was my waiter to know?

To Italian cheese lovers, Parmigiano-Reggiano isn't just ''the'' Parmesan cheese. It is ''the'' Italian cheese.

Any other cheese called ''Parmesan'' - made here or, even worse, in some other country - the Italians will quickly inform you, is quite simply poor forgery.

So hungry is this country for the slightly sharp, somewhat nutty-salty flavor of this cheese that only about 4 percent of production is exported worldwide.

That's just fine with the Italians. They are quite content to devour most of the 21/2 million wheels produced here each year as quickly as it rolls out of this area.

You may have a hard time finding a pepper shaker on your table in this part of Italy, but few tables are set without salt, toothpicks, and Parmigiano-Reggiano.

A few of the local citizens take their fondness to the extreme. Trucks of the cheese are occasionally hijacked. And how are the police rewarded when they nab the nefarious culprits? They get a free wheel of cheese. Certainly a bounty worthy of the chase.

On a recent tour of one of the 1,032 factories that make up the Parmigiano-Reggiano consortium, I learned much about this royal straw-colored cheese.

The Italian government controls the production of Parmigiano-Reggiano with both motherly pride and strict fatherly discipline. Only specified areas around Parma, Modena, Reggio Emila, Bologna, and Mantua are allowed to produce it.

Here, climate, an iron-rich soil, and cows come together and start the slow first steps of production.

''You can move the cows,'' I was told, ''but you can't move the climate, soil , and pastures. So nowhere else in the world can you make the cheese.''

Only the rich milk from cows grazing between April 1 and Nov. 11 is used in production.

The sight of a storeroom of Parmigiano-Riggiano is enough to make you gasp. Thousands of these pudgy wheels stand row upon row piled to amazing heights.

Weekly they are taken from their perch, cleaned, turned, and put back to age in diffused light and controlled temperature for a minimum of 18 months.

The Italians know no bounds when it comes to enjoying this cheese. They toss it as liberally as rice at a wedding. They nibble nuggets of it before a meal with thin slices of prosciutto, and munch wedges after dinner with fresh fruit.

Hardly a dish of pasta escapes a toss of this cheese. Rice dishes, soups, savory pies, and vegetables are dusted with it.

If you see Parmigiano-Reggiano at your local cheese store, buy only what will be consumed in about two weeks.

Price runs about $11 a pound in New York. Try some freshly grated in any recipe that calls for Parmesan cheese and compare it to the common boxed variety. True Parmigiano-Reggiano is much stronger in flavor so a little goes a long way. Pasta Shells with Three Cheeses and Prosciutto 1/2 pound large pasta shells, about 24 1 2-pound container ricotta cheese 1/2 pound mozzarella cheese, cubed or grated 2/3 cup freshly grated Parmigiano-Reggiano 1 egg 1/2 cup chopped Italian, flat-leafed parsley Salt to taste Freshly ground pepper to taste 1/4 pound thinly sliced prosciutto Olive oil 2 35-ounce cans Italian tomatoes 1 or 2 cloves garlic, finely minced 1 teaspoon dried basil 1/2 teaspoon dried oregano

Preheat oven to 350 degrees F. Cook pasta shells in salted boiling water for 13 minutes. Drain, rinse under cold water, drain again.

In large bowl combine egg, parsley, salt, ground pepper, and cheeses, except for 1/3 cup Parmigiano-Reggiano. Mix thoroughly.

Cut prosciutto slices in half and carefully line each shell with l piece, then stuff with cheese mixture.

Lightly oil or butter a large, shallow baking dish, about 8 by 14 inches, and place shells in it, close together, open end up, in rows.

In blender, process until thoroughly blended 1 1/2 cans Italian tomatoes, garlic, herbs, and any remaining prosciutto until throughly mixed. Cover pasta in baking pan with tomato mixture. Remaining tomatoes may be blended and added to cover if necessary.

Top with remaining 1/3 cup Parmigiano-Reggiano cheese and more cubes or slices of mozzarella if you wish. Drizzle with olive oil or dot with butter.

Bake uncovered about 30 minutes. Serves 4 to 6.

Black Olives and Anchovies Canapes 24 Greek-style black olives, pitted 1/2 cup freshly grated Parmigiano-Reggiano 1/4 cup butter 1 1/2 tablespoons anchovy paste 12 slices toasted white bread, 1/2 inch thick, 3 to 4 inches wide 1/2 medium sweet green pepper, cut lengthwise into thin strips 1/2 medium sweet red pepper, cut lengthwise into thin strips Put 18 pitted olives, cheese, butter, and anchovy paste in a food processor or blender and process until smooth.

Spread mixture on toasted bread slices cut into triangles and garnish by placing a halved black olive in center and 2 thin slices of green and red pepper on either side of olive. Fillets of Breast of Turkey with Parmigiano-Reggiano 1 pound breast of turkey cut into 4 slices 1 egg, lightly beaten 1 cup bread crumbs Vegetable oil 1 tablespoon butter 5 ounces Parmigiano-Reggiano cut into slivers

Dip turkey slices into egg and then bread crumbs.

Heat oil in skillet over medium heat and saute turkey slices. When done, transfer to butter-smeared baking dish. Cover with cheese and place in oven preheated to 400 degrees F. for about 10 minutes or until cheese has lightly browned. Serves 4 to 6.