Tuscany, that charming northern Italian province, is noted for its artistic treasures, scenic beauties, agricultural wealth and its cookery. The native dishes are based on such high quality native products as beef, ham, wheat, chestnuts, herbs, olive oil, Chianti wine and vegetables. I am particularly fond of the specialties made with fat, tender white beans called fagioli (fah-jo-lee).

In contrast with other Italians, Tuscans dine simply on dishes cooked with a minimum of sauces and seasonings. Their favorite fare emphasizes the natural goodness of the highly prized foods they grow. Nevertheless, Tuscan dishes are artistic and prepared with enviable ingenuity.

Haricot white beans and closely related types were introduced to Italy and rapidly gained favor as a substitute for the native fava beans. They became a staple of the Italian diet. A Duke of Florence made white haricot beans fashionable in Tuscany, and, ever since. Tuscans of all classes have been avid bean devotees.

Tuscans consume beans in such large quantities that they are mockingly called mangiafagioli (bean eaters) by other Italians, who regard the legume as peasant fare.

I became acquainted with the classic manner in which the beans are cooked and served while dining in a Florentine Buca , an atmospheric restaurant specializing in traditional cookery. Buca is an Italian word meaning "hole."

An ancient, uniquely Tuscan dish called Fagioli net fiasco (beans in a flask) exemplifies the high regard for bean cookery. Fresh or dried beans, and sage, are cooked in a flask, generally an empty Chianti bottle, as a means of preserving the dish's flavor and aroma.

Traditionally these beans are cooked over a bed of hot coals but the flask can be put in a slow oven or in a kettle of simmering water. Although somtimes eaten hot, the beans are generally served cold with a dressing of uncooked olive oil, salt and pepper.

Other distinctive bean dishes include: fagioli all' uccelletto, beans cooked like small birds. There is no plausible reason for the name except that the dish includes sage, a common ingredient in the cooking of small birds. A well-known cold dish called fagioli freschi al tonno, fresh beans with tuna fish, is generally served in large helpings as an antipasto but is also a good summer luncheaon entree.

Beans appear in all aspects of the Tuscan menu except deseert. There are several excellent bean soups made with pasta and beans, rice and beans, vegetables and beans, and cheese and beans. Beans, cooked in red wine or pureed, are served with the famous Florentine beef steaks, and as accompaniments to ham and game. As side dishes, beans, hot or cold, are flavored with herbs and salt park, garlic and tomatoes, onions and butter, or sage and olive oil.

In some American stores the white beans, called cannellini, may be purchased either canned or dried. White pea or navy beans may be used as substitutes but the flavor will not be the same. Use 1 pound of dried white beans to make 5 cups or two 1-pound, 4-ounce cans of cannellini.

Here are recipes for three of my favorite Tuscan bean dishes. TUSCAN BEAN SOUP WITH CHEESE (8 to 10 servings) 1 pound dried white beans 1 large onion, peeled and chopped 2 garlic cloves, crushed 1 large carrot, scraped and diced 2 celery stalks, with leaves, cleaned and chopped 1 cup diced, smoked ham 1/4 cup olive oil 1/2 teaspoon ground red pepper

%1 teaspoon crumbled dried rosemary Salt, pepper to taste 1/2 cup chopped fresh parsley 3 to 10 slices toasted crusty white bread 1/2 cup grated parmesan cheese (preferably freshly grated)

Wash and pick over beans and put into a large kettle. Cover with water; bring to a boil and boil 2 minutes. Remove from heat and let stand, covered, 1 hour. Drain beans, reserving water. Add enough fresh cold water to make 3 quarts.

Satute onion, garlic, carrot, celery and ham is heated olive oil in a large kettle for 5 minutes. Add beans with water, red pepper, rosemary, salt and pepper. Bring to a boil. Reduce heat and simmer, partially covered, about 1 1/2 hours, until beans are tender.

Remove about half the beans from the soup and puree; return to soup. Add parsley. Simmer over low heat, stirring, 1 or 2 minutes. Put toast in bottom of soup plates. Ladle soup over them. Serve cheese to sprinkle over the soup. TUSCAN WHITE BEANS WITH TUNA (4 to 6 servings) 4 cups canned cannellini or other cooked or canned white beans, drained 1/2 cup chopped onions 1/2 cup chopped fresh parsley 2 tablespoons fresh lemon juice Salt, pepper to taste 1 can (7 ounces) tuna in oil 2 hard-cooked eggs, shelled and cut into wedges 1 small red onion, peeled, sliced and separated into rings

Combine beans, onions, parsley, lemon juice, salt and pepper in a large bowl. Spoon onto a plate or into a shallow serving dish. Divide tuna into chunks and arrange over bean mixture. Sprinkle with oil from tuna. Garnish top with egg wedges and onion rings. Serve at room temperature or chill BEANS COOKED LIKE SMALL BIRDS (4 to 6 servings) 2 garlic cloves, crushed 1/2 cup olive oil 1/2 teaspoon crumbled dried sage leaves 3 large tomatoes, peeled, seeded and chopped Salt, pepper to taste 4 cups canned cannellini or other cooked or canned white beans, drained 1 1/2 tablespoons fresh lemon juice

Heat oil in a large saucepan or skillet. Heat garlic for several seconds. Add sage and cook several longer. Stir in tomatoes, salt, pepper and beans. Cook slowly, covered, 7 or 8 blend flavors. Stir in lemon juice and remove from heat.