GIULIANO BUGIALLI is an angry man. He is misunderstood.His countrymen and women are misunderstood. His home town is misunderstood.

It all boils down to what he feels is a bad translation of Italian cooking and eating habits.

Bugialli eats superbly. In part that's because he is a teacher of cooking in New York, in his native Florence and - most recently - here in Washington and in part because he eats in what he considers the true Italian manner.

"You go to a so-called Italian restaurant here," he said. A cloud erased the smile that's usually found above his well-trimmed black beard. "All that food on one plate - meat, pasta, vegetable: We don't make a messlike that. We're very strict. We separate the meal into many courses and use different plates for each one. Here they serve pasta and then a huge plate of food after. We don't do that. We may have a roast meal, some salad, cheese and fruit. But we don't go on to eat a big dessert. People laugh, but our food is light. We eat small portions.

"When I am teaching at home in Florence I eat pasta every day and I lose weight. Here I gain weight because Americans always insist on a rich dessert."

He wasn't throwing things yet, but as he focused on a tomato, his questioner considered taking shelter.

"Tomatoes and garlic!" he said. "We don't make every meal with them. In Florence we don't even use tomatoes and garlic very much. Americans who come to my classes are shocked.

"Lasagna," he continued, a touch of sadness creeping into his voice. "What is it? It's awful. Ours [in Italy] has at least twelve layers of pasta. 'Florentine!' A single leaf of spinach will do it. The dish is described as 'Florentine' on a menu here. It's depressing."

Bugialli has been trying to turn things around through his cooking classes and through an excellent new book, The Fine Art of Italian Cooking (Quadrangle, $15). "My idea is to give a different idea of what Italian cooking and life really is," he said. His weeklong classes in Florence (one of which in October, focuses on fresh truffles and game cookery) have been attracting a large number of restaurateurs and cooking teachers, so his missionary work may begin to show results.

In this area he has been teaching to full houses at L'Academie de Cuisine in Bethesda in an eight-session, one-day-a-week course that will be repeated beginning March 17 and again next fall.

A Bugialli lecture-demonstration is sprinkled with good humor, historic references (he is a scholar of Renaissance cooking), a few warnings that may be more taboo than truth ("you must stir this sauce in only one direction") and some amazing displays of culinary talent, not the least of which is rolling through a machine a sheet of pasta that will grow to twenty feet or so without breaking.

While many of his recipes are not complex, they do require considerable effort and are intended to be prepared at the last minute. "People here want to cook," he explained, "but they also want to be with their guests. So they look for recipes they can make ahead and reheat. I don't do that. Instead I try to make them comfortable with what they do, so they are not embarassed when guests come into the kitchen."

At the drop of an eggplant, Bugialli will tell you that Florence was "where haute cuisine started," and explain that Tuscanyoffers a cariety of foods "from mountain, hills and the sea" unmatched in any other region. The cooking is "pure and beautifully balanced," while that of Rome is baroque. He drops hints that Bologna, often cited as the gastronomic capital of Italy, has suffered from "foreign influences." Too many French sauces and Austin pastries over the centuries. Too bad. Florence wins. To him the fine art of Italian cooking means Tuscan cooking.

For those who might like to sample it from the pen of a purist, here are several recipes from his book, including one for spinach done the Florentine way. Spinaci alla Fiorentina Spinach, Florentine-style Serves four to six 2 pound fresh spinach 1 clove garlic 3 tablespoons olive oil 3 tablespoons butter 3 tablespoons flour 2 1/2 cups milk 3 tablespoons freshly grated Parmigiano cheese Salt and white pepper to taste Pinch of nutmegs

First, make a besciamells (white sauce). Melt the butter in a heavy saucepan over a low, steady flame. (It is important to use a heavy pan and a low flame so the sauce will thicken without burning.) When the butter has reached the frothing point, add the flour. Mix very well with a wooden spoon, then let the pan from the flame and let rest for ten to fifteen minutes.

While the butter-flour mixture is resting, heat the milk in another pan until it is very close to the boiling point. Put the first saucepan back on the flame and very quickly add all of the hot milk. Be careful not to pour the milk in slowly; that can create lumps in the sauce. Begin mixing with a wooden spoon while you pour and keep mixing, always stirring in the same direction, to prevent lumps from forming.

When the sauce reaches the boiling point, add the salt and white pepper and continue to stir gently while the sauce cooks slowly for twelve to fourteen minutes more. Remove from the flame; stir in the cheese. Let cool in the covered pan.

Clean the spinach well, removing the heavier stems, then boil in a large quantity of salted water for twelve to fifteen minutes. Drain, then place under cold running water to cool. When the spinach is cold, squeeze it very dry and chop it coarsely.

Cut the garlic clove into small pieces and place them in a frying pan, along with the olive oil. Place the pan on medium heat and let the garlic saute very slowly, until golden brown (about five minutes).

Add the chopped spinach to the pan, season with salt and pepper and saute the spinach, stirring constantly, for ten to fifteen minutes. Transfer to a bowl to cool.

Preheat oven to 375 degree.

Place half the besciamella in the bowl with spinach. Add nutmeg and mix very well, until the besciamella is incorporated into the spinach.

Butter the bottom and sides of a baking dish. Place the spinach in the dish, making a smooth, even top surface, then pour on the remaining besciamella as a top layer. Put the dish in the preheated oven and bake for about twenty-five minutes; the top layer should be lightly golden brown.

Serve hot, right from the baking dish. Acciugata Anchovy sauce with spaghetti Makes about one cup

A very simple sauce in which the anchovies are crushed and mixed into hot olive oil, this is also widely versatile, being equally at home with dried pasta, a vegetable such as cauliflower, or with leftover cold veal cutlets alla milanese or braciole fritte. 5 anchovies in salt or 10 anchovy fillets in oil 1 cup olive oil Freshly ground salt, if necessary

If anchovies under salt are available, fillets them while holding them under cold running water to remove excess salt. Drain on paper towels.

Put the olive oil in a heavy aluminum saucepan and heat on a low flame. When the oil is very hot, almost sizzling, remove the pan from the flame. Immediately add the the filleted anchovies and mash them into the oil, using a fork, until they make a paste.

Sprinkle with pepper, then taste for salt and add it if necessary. (If the anchovies have been preserved in salt, it probably will not be.)

Pour the hot sauce over one pound of cooked and drained spaghetti (to serve four). Toss thoroughly. Sprinkle with freshly ground pepper and serve immediately; do not add any grated cheese. Arista Loin of pork with garlic, rosemary and black pepper Serves eight to ten 8 to 10 large cloves garlic 2 heaping tablespoons rosemary leaves 1 1/2 tablespoons salt

1 level tablespoon freshly ground black pepper 4 pounds front part pork loin, boned but untied 10 to 12 whole black pepper-corns 1 tablespoon olive oil

Preheat the oven to 350 degrees.

Cut the garlic cloves into four to six pieces lengthwise, then combine in a bowl, with the rosemary leaves, salt, and ground pepper.

Place the loin on a board and open it out flat, with the inside facing up. Spread half the garlic mixture over the inside surface, then scatter over the whole black pepper-corns. Roll the loin and tie with thread, as follows:

Wrap the thread around the meat, starting at one end, and pull tight. Do not break the thread but ring it down lengthwise two inches and wrap it around the meat again. Continue this process until the entire length is tied around, at a distance of every two inches or so.

When rolled and tied, make about twelve punctures in the outside of the meat with a thin knife, about a half-inch deep. Fill these holes with most of the remainder of the spice mixture, and if any of the spice mixture is left, sprinkle it over the outside surface of the loin.

Put the olive oil in the bottom of a roasting pan, then set the meat in it. Place the pan in the preheated oven for about twenty-five minutes to the pound. The pork should not be overcooked, and generally in Italy is cooked less than in America; it is advisable to cook the meat completely, but to be careful not to leave it in the oven beyond that point. Not only the weight, but the width of the roll affect cooking time.

After about an hour in the oven, turn the meat over. For the last five to ten minutes, raise the temperature to 400 degrees, to brown the outside.

Remove the pan from the oven and immediately transfer the arista from the pan with its drippings. Let cool for ten minutes before slicing in thin slices and serving.

Note: Arista may be eaten cold for several days following, and many Florentines prefer it that way.