Preheat the oven to 400 F and line a baking sheet with foil or parchment paper for easier cleanup or just spread some oil on the pan.
Mix the Worcestershire sauce, ketchup, mustard, jam and onion in a small bowl.
Coat each piece of chicken with the sauce so it's well coated on all sides and lay them on the baking pan.
Dump the rest of the sauce over the chicken.
Bake for 45 minutes to 1 hour, basting now and then if you remember. (I didn't.)