Heat oven to 350 degrees F. Whisk together olive oil, lime juice, cilantro, garlic and chili pepper. Spray a 9 x13 baking dish with cooking spray; add chicken breasts. Brush chicken with herb mixture. Bake for 35 minutes or until chicken reaches an internal temperature of 165 degrees F. Remove chicken; let it rest covered with foil for 10 minutes, thinly slice. Meanwhile spray large skillet with cooking spray over medium heat. Make quesadillas by laying a corn tortilla in the pan, add 1 slice of cheese, tomato slices, 1/2 a sliced chicken breast, then another corn tortilla. Use a spatula to press down on quesadilla without letting ingredients spill out. Cook 2-3 minutes; flip and cook 2-3 more minutes. Repeat with remaining quesadillas. Slice quesadillas into quarters and top with 1/2 cup shredded lettuce, 1/4 sliced avocado and 1 tablespoon non-fat Greek yogurt (optional).