NOTHING is more warming than Santa Fe's cuisine. A direct descendent of its three cultures, Santa Fe cooking celebrates and blends the flavors of its American Indian, Hispanic, and Anglo history. The main industry here is the tourist trade and the many restaurants cater to it, ranging from the inexpensive and delicious tofu tamales at the Baja Tacos stand to moderately priced Tomasito's hearty fare to the high art of La Casa Sena or Santacafe.Indians discovered and cultivated the foods of the region: pinon nuts, chilies, corn, tomatillos, tomatoes, cactus, black beans and pinto beans, many squashes, even potatoes are all New World contributions. Local fish and game like trout, antelope, venison, buffalo, poussin (similar to a game hen), rabbit, pheasant, and more grace the better restaurant kitchens. But what really sets Santa Fe cuisine apart is the expansive use of chilies in great variety. Chilies show up in sauces and marinades, in sweet chutneys, jellies, and delicious breads, in extravagant potato dishes, and in stuffing, salad dressing, salsa, and soups. "There are 20 varieties of chilies in regular use at Casa Sena," says restaurant president Gordon Heis. The influence of Southwestern cuisine has spread to California, he says, and many of the products used in nouvelle cuisine really began in Santa Fe. Casa Sena's chef, David Jones, says ve learned the traditional fare inside out, studied the ingredients. You really have to search out the chilies. I use a lot of northern New Mexican chilies from Chimayo and Dixon. The big jims, a dried red chile, come from Chimayo, for instance." Local farmers experiment with varieties of chile under Mr. Jones's tutelage, sometimes allowing chilies normally picked green to ripen to a rich red - always risky in a high altitude climate where a snap frost can kill the plants overnight. The chilies most often used among Casa Sena's 20 varieties are the pablano (fresh and moderately hot), chipotle (smoked red jalapeno, very spicy), and mild anaheims. Chef Jones uses even hotter chilies. "Many people think all chilies are hot," says Santacafs owner, Jim Bibo. "They're not. Some are sweet, some bitter. Many are hot - some very, very hot." Santacafs signature dish is a chile brioche that combines fresh pablano with dried red chilies and red bell peppers. It's a tasty, surprising bread served with butter and a cooler, whole-grain bread at all meals. Mexican cuisine, which combines Indian and Spanish tastes, is heavily in evidence in Santa Fe. But there's a difference. Black beans accompany dishes as often as the ubiquitous refried pinto beans. A delectable fry bread called sopapilla accompanies most meals to cool the heat produced by the fierce little chile, and it can be eaten as a dessert with ice cream or smothered in honey. The enchiladas (stuffed with beef, chicken, or cheese) that absolutely everyone serves here will most likely be made with blue- corn tortillas instead of the usual yellow tortilla. Blue corn, an Indian staple, is more nutritious than yellow corn, and seems to be a tad sweeter. It appears in spicy muffins, corn-bread dressings, breading of fish and fowl, and even in another Santa Fe staple corn dish, posole - a hominy dish native to the region that is essential at all holiday gatherings and may be found o n most restaurant menus. Chef Jones creates a blue-corn blini for Casa Sena's holiday menus topped with three American caviars. Corn, of course, is an indigenous treasure. In the fall when the harvest is in, corn chowders multiply. But corn breads and tortillas are a year-round staple. Another Santa Fe staple is the tiny pinon nut, product of a local scrubby pine (pinon) tree. New Mexican pinon nuts are smaller and tastier, according to local chefs, than varieties grown in the Mediterranean and China. Pinon flavors almost anything - from salads and appetizers to the breading that encases free-range chicken breast (see recipe at left) to turkey stuffing a la Casa Sena to a range of desserts. The pinon's oil content is very high, so in making the many desserts, cooks must carefully weigh that fact. All kinds of wonderful tarts and crusts for such exotic wonders as Casa Sena's award-winning avocado-lime cheesecake with pinon crust come from the humble pinon nut first harvested - and still harvested - by the many Indian tribes of the region. The Spanish brought lamb, cattle, and wheat flour to the region. Anglos have contributed a wide variety of vegetables and cheeses. And Indian cultures have provided most of the indigenous ingredients that make Santa Fe cooking so distinctive. Then, too, Indian preparation methods still make for special cookery: Casa Sena's signature dish is trout stuffed with wild mushrooms, wrapped in grape leaves, and then encased in terracotta clay and baked. When the fish is cooked, the clay casing is broken and discarded and the fish served to perfection.