2 ripe tomatoes, seeded and diced
1 firm-ripe Haas avocado, peeled and diced
1 tablespoon chopped red onion
2 teaspoons fresh lemon juice
1/4 teaspoon Tabasco sauce
1/4 cup sour cream
3 tablespoons chopped fresh cilantro
4 (6- to 7-inch) flour tortillas
1/2 teaspoon vegetable oil
1 1/3 cups coarsely grated Monterey jack cheese
Fresh cilantro sprigs (for garnish)
In a small bowl stir together tomatoes, avocado, onion, lemon juice and Tabasco sauce. Season with salt and pepper. In another small bowl stir together sour cream and cilantro and salt and pepper to taste.
Preheat broiler. Put tortillas on a large baking sheet and brush tops with oil. Broil tortillas on a rack set 2 to 4 inches from heat until pale golden. Turn tortillas and broil until other sides are pale golden. Sprinkle tortillas evenly with cheese and broil until cheese is melted and bubbling. Spread avocado mixture evenly over tortillas and top each with 1 of remaining tortillas, cheese side down, to make 2 quesadillas. Transfer quesadillas to a cutting board and cut each into 4 wedges. Top each wedge with a heaping teaspoon of sour cream mixture and garnish with cilantro sprigs.