1. Preheat the oven to 450 degrees F.
2. Spray a baking sheet with cooking oil spray. Place 1 tortilla on the baking sheet. Pour about 1/4 cup of the Flexible Mexican Filling on half of the tortilla, spreading it to within about 1/2 inch of the edge. (The filling will spread out a bit during baking.) Fold the tortilla in half over the meat mixture, pressing it lightly with your hands so it adheres. Repeat with 3 more tortillas on the first baking sheet. Then repeat the process with the remaining tortillas on the second baking sheet.
3. Place both baking sheets in the oven and bake until the tortillas are crisp, 5 to 7 minutes.
4. While the quesadillas bake, core and dice the tomatoes, placing the pieces in a serving bowl. Shred the lettuce, placing the pieces in another serving bowl. Pour the salsa into a third serving bowl.
5. Remove the baking sheets from the oven and, using a pizza cutter, cut each quesadilla into 3 wedges. Place 4 wedges on each plate. Serve at once, topping each quesadilla with tomato, lettuce, and salsa, *(I prefer sour cream too!) as desired.