Sprinkle shredded cheese evenly over one half of the tortilla. Add cranberry sauce or dried cranberries, turkey and spinach, then fold the tortilla in half over the filling.
Heat a medium skillet over medium heat (300 degrees in an electric skillet). Lightly spray with cooking spray, then place tortilla in the skillet. Cover and cook for 2 to 3 minutes on each side, or until the outside is golden brown and contents are heated through.
Refrigerate leftovers within 2 hours.
Substitute beans, tofu, or other cooked meat for the turkey.
For extra flavor, add a dash of cayenne pepper or chili powder before folding the quesadilla in half.