Put peach preserves, brown sugar, soy sauce and vinegar in a large glass bowl and microwave for 30 seconds. Remove from microwave and whisk until preserves and sugar and dissolved. Whisk in ginger, garlic and red pepper flakes. Add chicken and marinate for 15 minutes.
Preheat broiler to high. Cover a baking sheet with aluminum foil and spray with nonstick cooking spray. Remove chicken from marinade and place on baking sheet. Broil about 3 inches from the heat until cooked through (about 5 minutes on each side).