Place pork chops in baking pan. Top each with 1 lemon slice and 1 onion slice, 1 T. catsup and 1 T. brown sugar. Cover and bake 30 minutes in 375 degrees oven. Uncover and continue baking until liquid has been absorbed, and pork chops browned about 30 minutes longer. Baste with pan juices during second half of baking. Makes 4 servings.