IT WAS, as Nadine Kalachnikoff sees it, a choice between moving to Europe and finding a wealthy man to marry or going into business in this country to support herself and her two small children. Kalachnikoff chose the latter. "I had to have an income and I didn't think marrying someone very rich in Europe would be very good for my children." So she mortgaged her house, threw herself on the mercy of the bank, and opened Pasta Inc. a month ago.

"Some days, I want to shoot myself," she says as she rinses the freshly made pasta, "some days it's fabulous but you do have to have a passion for cooking" . . . and for hard work.

Two years ago Kalachnikoff was divorced from Howard Joynt and from a life spent either cooking at home or running the restaurant, Nathan's II. She says she was left with almost no self-confidence until her friends convinced her it was she who had made the restaurant the success it once was. She thought of opening a restaurant but decided she would never get to see her children if she did. A store, she felt, would give her more flexibility. And perhaps it will . . eventually. Now it takes 12 to 14 hours and her children, who are 6 and 3, nap in the afternoon so they can spend some time with their mother when she gets home at at 10 or 11 p.m.

Kalachnikoff's days are consumed with trying to get Washington's first fresh pasta emporium and European style carryout off and running. Located at 2805 M Street in Georgetown, the store has a distinct chic East Side New York ambience. One of the windows is filled with the pasta machine and drying rack. A tortellini machine arrived last week. The elegant quality food products are set against a pristine background of white walls, white ceramic tile floor, white light fixtures and white ceiling fans. Shiny metal racks hold wines, mostly Spanish and Italian; glorious French pastries made by a pastry chef in the kitchen each morning; an expensive but extremely good and handsomely packaged line of foods from New York's Silver Palate, a tiny West Side store so successful that it has gone into the wholesale business with fruit vinegars, preserves, pates, etc.

The refrigerator case holds treasurers like authentic Devonshire cream and, of course, the small containers of the prepared pasta sauces Kalachnikoff and her chef prepare each day; pesto, summer and winter tomato sauces, meat trastevere (chicken with sherry and cream), nutmeg, nine varieties that range in price from $2.85 to $6.50.

Another case contains the elegant prepared salads, which as one customer said, make it possible with the pasta, to have a dinner party for 10 on a half hour's notice. Not everything is Italian: a ratatouille, lentils and sausage, duck pate en brioche, beef salad with mustard sauce and peppers, chicken breasts with tarragon and herb dressing. But there's also lasagna, pasta salad and Sicilian eggplant along with freshly grated parmesan from Milan, and mozzarella made in the kitchen at the back of the store.

In addition to the four kinds of pasta (spinach, tomato, egg and whole wheat), which sell for $2.69 a pound, and sauces, what Kalachnikoff has gathered together are the makings of an elegant picnic, including the baskets.

Her interst in cooking -- all of the prepared food, with the exception of the pastries, is made from her recipes -- goes back to her childhood when she and her three sisters had their choice: If they couldn't cook, they either had to wash the dishes or set the table. Kalachnikoff preferred the cooking. Her mother, who was Spanish, was an "extraordinary, extraordinary cook." The rest, she says, she learned by watching other people cook.

As a child Kalachnikoff led a cosmopolitan life. With her father, a Russian emigre, and her mother, she and her sisters traveled to Europe every year. They were exposed to many cultures and she speaks four languages, all of which she uses at Pasta Inc.

The idea for the store came to her the night she says she wanted some risotto and there was none in the house, and no place to buy it. "At first I thought of a place that would have little packages of premeasured ingredients with recipes and people could put them together themselves. It would be great for people who come home after spending all day at the hairdresser or with a lover. They could still get dinner on the table," Kalachnikoff said with a laugh. She decided the idea might do well in New York, but not here because "Washingtonians don't live that way."

She settled on an elegant carryout, where everything but the pasta is already cooked, though she wants the place to become a lot more. Kalachnikoff particularly likes to cater small parties, no more than 30 people "because it just doesn't taste the same when you cook for more. I want to keep the high quality," she said, "even if I sink."

One day she would like to be selling her pasta wholesale and have tiny shops in the suburbs which carry just the pasta and sauces. "I want to do this," she says, "before I am too old to enjoy my farm," another dream. At 34 she should have enough time to realize her fantasies. But she says she's still scared. "I don't want to lose my house. I have moments when I think maybe I'm absolutely nuts.That's when I'm terribly, terribly tired.

"The most important thing," she says "is not be dependent on any man."

Pasta Inc. is open from 11 to 8 Mon.-Sat. and 12 to 6 Sun. These recipes have been adapted from those sold at the store. PASTA SALAD (10 to 12 servings as main course) Forget the calories! 1 pound fresh egg pasta, tagliatelle cut 1pound fresh spinach pasta, tagliatelle cut Dressing: 3 cups mayonnaise 2cups creme fraiche 3 cups sliced fresh mushrooms 3/4 cup lemon juice 1/2 cup white wine vinegar 2 tablespoons dried tarragon leaves 5 tablespoons dried basil leaves 4 tablespoons fresh parsley 6 green peppers, cut in julienne strips 3 red peppers, cut in julienne strips Salt and freshly ground black pepper to taste Cream

The night before, marinate mushrooms in 1/2 cup lemon juice. Cook the pasta in a large pot of rapidly boiling salted water for about 3 minutes; check texture before rinsing under cold water and draining.

To make dressing drain lemon juice from mushrooms and discard juice. Combine mushrooms with mayonnaise, creme fraiche, herbs, peppers, 1/4 lemon juice and wine vinegar. Mix gently but thoroughly. Chill overnight, or at least for 6 hours so flavors will meld. If dressing is too thick, thin with a little heavy cream. WINTER TOMATO SAUCE (About 5 cups) 2 tablespoons plus 1 teaspoon olive oil 5 teaspoons butter 1 onion, finely ground 1/2 head of garlic, about 5 large cloves 1/2 cup dry red wine 2 cans (29 ounces each) tomatoes 10 ounces tomato puree 1/2 bay leaf 1 1/2 teaspoons dried basil 1 teaspoon sugar 1 tablespoon plus 1 teaspoon oregano leaves Salt and freshly ground black pepper to taste

Saute onion in oil and butter until onion is translucent. Add whole pieces of peeled garlic and saute for about one minute. Add wine and stir well. Crush tomatoes with your hands, leaving them lumpy. Add with puree to pan. Bring to a boil. Reduce heat to simmer and add remaining ingredients. Cook, uncovered, about 1 1/2 hours; stir occasionally. QUATRO FROMAGGIO (5 to 6 inch in diameter cake)

Misnamed by the chef, but it sounds so much better than tre fromaggio (three cheeses), it stuck. 1 pound ricotta 1 pound gorgonzola, softened 1/2 plus 1/3 cup chopped walnuts 8 ounces whipped cream cheese, softened 1/4 pound unsalted butter, softened 1/2 cup heavy cream 1/3 cup pignoli nuts 2 tablespoons silvered almonds

Cut a round wax paper to fit the bottom of a 5 or 6 inch diameter souffle dish. Spread 2/3 of gorgonzola in smooth layer in bottom of dish. Top with 1/2 cup walnuts; press into cheese. Smooth on a layer of cream cheese. Smooth on a layer of butter. Sprinkle on remaining walnuts; press in. Smooth on a layer of remaining gorgonzola. Top with layer of ricotta. Chill for four hours or longer. To unmold, dip the dish briefly in hot water; run knife around edge and unmold on serving plate. Remove wax paper.Beat cream and spread whipped cream on top of cake. Decorate top and sides with pignoli and almonds. Slice very thinly with a very sharp knife. Serve with Italian or French bread. Excellent with a green salad. CAPTION: Pictures 1 and 2, Photos of Nadine Kalachnikoff by Larry Morris -- The Washington Post; Pasta; Copyright (c) Now! Designs SF; Picture 3, no caption, By Larry Morris -- The Washington Post