1. Preheat grill to medium high.
2. Moisten a paper towel with oil, hold towel with tongs, and wipe grill with oil. Arrange chicken breasts on grate. Cook approximately 10 minutes on each side, or until chicken is no longer pink in its thickest part and its juices run clear. When chicken is cooked, slice it into thin strips.
3. While chicken is grilling, prepare bean filling. Empty undrained can of pinto beans into a small saucepan and bring to a simmer. Drain beans well and return to pan. Stir in ketchup and mustard. Mash beans to a chunky consistency with a potato masher. Set aside.
4. To assemble quesadillas, layer one half of each tortilla with about 1/4 cup shredded cheese. Divide chicken, then bean mixture, among the 6 tortillas, then top beans with remaining cheese. Fold each tortilla in half and press down lightly to compact filling. Grill quesadillas 2 to 3 minutes on each side until golden grill marks appear. A large spatula makes it easier to flip them.
5. To serve, cut each quesadilla into 3 or 4 wedges. Serve warm with bowls of raspberry-lime salsa and sour cream. May be prepared a day in advance and reheated at 350 degrees F for 15 to 20 minutes. If frozen, reheat for 25 to 30 minutes.
Source: Hannaford fresh Magazine, July - August 2008