Preheat the oven to 350 degrees F.
Place chicken in a roasting pan or on a sheet pan. Sprinkle chicken with seasoning salt. Bake for 35 to 40 minutes, or until almost cooked through. Remove from oven and refrigerate until ready to finish, or transfer immediately to a very hot grill. Baste generously with BBQ sauce and continue cooking until the sauce begins to caramelize and until an instant-read thermometer registers 180 degrees F when inserted deep into the thigh, away from the bone, and registers 160 degrees F when inserted in the breast, away from the bone. Remove from heat and serve.