I have agree with Erin that the rub that goes on this chicken before cooking it and then placing it in the quesadillas really adds a ton of flavor to these quesadillas compared to other chicken quesadillas I've made before in the past on my own.
Here's the recipe as taken from Dinner & Dessert:
2 chicken breasts, pounded thin (I think it's very important to pound chicken before cooking it no matter what the recipe.)
2 teaspoons cumin
2 teaspoons chili powder
1 teaspoon oregano (I used dried oregano leaves)
Olive oil (enough to coat the pan)
4 tortilla shells
Mexican cheese (use as much as you prefer)
1 can black beans
Mix together cumin and chili powder. Lightly rub over chicken. Sprinkle oregano over chicken. Pan fry in olive oil until done. Let cool. Cut in small pieces.
Coat a large frying pan (as big or slightly bigger than the tortilla shell) with cooking spray. Add tortilla, cover the whole shell with cheese (use as much as you like), then add chicken and black beans on one side. Cook on medium or medium-low heat until tortilla bottom is brown and cheese is melted.