Fajitas - you barbecue a meat-market discovery - skirt steak. Then build a burrito

Sunset, July, 1985

Along the Mexican border, fajitas (fahee-tas) means skirt steaks. In other parts of the West, however, the word has entered the dining vocabulary as a catchall term for make-it-yourself burritos with grilled meat. Marinated, embellished with grilled onions, and wrapped in a tortilla with condiments, the main ingredient is usually the dish's namesake skirt steak.

No one knows exactly how burrito-style fajitas evolved. Credit for the invention may well go to Mexican ranch hands working in the Southwest. Out in the fields, the workers grilled richly flavored and modestly prices skirt steaks over mesquite coals. They sliced and wrapped the meat in tortillas, to eat out of hand.

True to their probable outdoor origin, fajitas make the barbecue central to this simple party menu. Marinate steaks in a lime-and-garlic mixture, then quickly grill. Onion halves and green onions cook alongside. Guests heat tortillas on the grill, then fill them with meat, onion, beans, salsa, guacamole, and sour cream.

While guests await the main course, they can nibble cucumber spears they drench with generous squeezes of lime juice and sprinkle with cayenne. For dessert, offer honeydrew wedges and strawberries.

Skirt steaks are worth seeking out. The steak is a long fibrous muscle that attaches to the diaphragm inside the rib cage. Since there are only 2 of these steaks (weighing 1 to 1-1/2 pounds apiece) in each carcass, they may be in short supply. It's best to order them ahead; ask your meatman to leave them whole and flat; they do not require tenderizing. If steaks are split lengthwise, rolled, and skewered (looking like big beef lollipops), simply unroll and grill flat. If unavailable, use flank steak.

Fajitas 3 pounds skirt steak of flank steak 1/2 cup lime juice 1/3 cup salad oil or olive oil 1/3 cup tequila or additional lime juice 4 cloves garlic, pressed or minced 1-1/2 teaspoons ground cumin 1 teaspoon dry oregano leaves 1/2 teaspoon pepper 4 or 5 small unpeeled onions, cut in half lengthwise 8 to 10 green onions, roots washed or trimmed Frijoles (recipe follows) 16 to 20 flour tortillas (8 to 10 in.) Salsa fresca (recipe follows) Guacamole (use your favorite recipe) Sour cream Cilantro springs (coriander)

Cut skirt steaks crosswise to fit into a 9- by 13-inch dish or pan. Mix lime juice, oil, tequila, garlic, cumin, oregano, and pepper. Add to meat; turn steak to coat. Place onion halves, cut down, in marinade. Cover and chill at least 4 hours or up to overnight, turning meat occasionally.

With a string, tir green onions together about 3 inches from roots to form a brush. About 1 hour before serving, measure out enough charcoal briquets to make a single solid layer on a barbecue firegrate; stack and ignite. When coals are covered with gray ash (30 to 45 minutes), spread level. Set grill 4 to 6 inches above coals.

Place onion halves on grill. Cook about 7 minutes and turn over. Place beef on grill. Baste meat and onion halvs with marinade, using onion brush. (Extinguish any flmes with a water-filled squirt bottle.) Cook onion halves until soft and browned, 6 to 8 minutes a side. Cook beef until browned and done to your liking, 3 to 5 minutes a side for rare. As meat and onions finish cooking, transfer to a board. Cover loosely to keep warm.

If there is room, place frijoles on grill away from main heat; stir often until hot. Roll onion brush in marinade and lay on grill. Turn brush often until green tops are wilted, 3 to 5 minutes. Place brush on board with meat; remove string. Cut meat into thin slices; slice flank across grain.

Let individuals heat their own tortillas on the grill, turning often with tongs just until soft, 15 to 30 seconds. Place a few meat slices down center of each tortilla, top with some frijoles, a few pieces from onion halves, salsa, guacamole, sour cream, and cilantro. Fold up bottom and fold in sides to enclose. Eat grilled green onion alongside. Makes 8 to 10 servings.

Frijoles. In a 2- to 3-quart pan, cook 4 strips bacon, cut into 1/2-inch pieces, stirring over medium heat until limp. Add 1 large onion, chopped, and 2 teaspoons chili powder; cook, stirring, until soft.

Drain 3 cans (about 1 lb. each) or 4-1/2 cups cooked pinto beans and add to onions; add salt to taste. (If made ahead, cool, cover, and chill up to overnight.) Stir often over low heat (can be on the barbecue) until hot, adding a little water if needed to keep beans from sticking.

Salsa fresca. Mix 2 large ripe tomatoes, cored and diced (about 2 cups); 2 large tomatillos, chopped with husks removed (about 1 cup), or 1 more large ripe tomato, cored and diced; 1/2 cup chopped frsh cilantro (coriander); and 1 small onion, chopped. Add to taste 5 to 7 tablespoons seeded minced fresh hot chilies; 3 to 4 tablespoons lime juice; and salt. Serve, or let stand up to 2 hours. Makes 4 cups.