Quesadillas, those puffy "little whims" as the Mexicans call appetizers, can be found in most Mexican restaurants in many variations. Sometimes called empanadas, these turnovers have evolved through the years. Traditionally, masa dough is flattened and folded over to enclose a variety of fillings. In California we make quesadillas with either corn or flour tortillas. They can be simple, with a melted cheese center, or more complicated creations like this one. Olive oil spray on the pan or griddle keeps the outside crispy without being overly greasy. If you dont have the spray, add a tablespoon of vegetable or light-flavored olive oil to the pan and make sure it is very hot before cooking the tortillas. These small triangles are wonderful served as a first course before a Mexican-style main course like Grilled Skirt Steak with Avocado-Tomato Salsa or as a main course for brunch or lunch. RECOMMENDED WINE: A spicy, rich central coast Chardonnay is perfect with this flavorful appetizer. 1. In a deep medium skillet or a large saucepan, bring the chicken stock (or enough of a combination of chicken stock and water to cover the chicken) to a simmer. If youre using water only, add 1/2 teaspoon salt. Add the chicken breast and simmer for 10 to 12 minutes or until just tender. Cool the chicken in the stock. Drain the chicken, remove the skin, and shred it into bite-size slices. 2. Heat the oil in large non-aluminum casserole over medium-high heat. Add the onions and saute, stirring frequently, for about 10 to 15 minutes or until well softened. 3. Add the beer, vinegar, sugar, and jalapenos to the onions and simmer over low heat until almost all of the liquid has evaporated. The onions should be very tender and slightly caramelized. Add the oregano, salt, and pepper. Taste for seasoning and let cool. 4. Lightly spray a 12 inch nonstick skillet or griddle wtih nonstick spray or add a tablespoonof oil and place over medium-high heat. Place a tortilla in the skillet and spoon 1/2 cup of the onion mixture evenly over one half. Sprinkle with 1/2 cup chicken and top evenly with 1/2 cup shredded cheese; fold the tortilla in half, pressign down with a spatula. Cook the quesadilla until lightly brown, then turn over and cook the other side until lightly brown. Place on a cutting board, slice into bite-size wedges, and keep warm under foil. 5. Repeat to cook the remaining quesadillas. Arrange on a large serving platter and serve immediately accompanied by guacamole, salsa, and sour cream. Advance Preparation: Can be prepared up to one day ahead through step 3 and refrigerated. Remove from refrigerator one hour before continuing. Posted to MM-Recipes Digest V4 #311 by "John Weber" on Dec 01, 97