Heat 1 tablespoon of the oil in a pan over medium heat. Stir in the onion and cook until golden brown. Set aside.
Heat 1/2 tablespoon of the oil to the pan. Season pork chops with salt, pepper, and garlic powder and place in the pan. Cook to desired doneness. Set aside and keep warm.
Heat remaining oil in the pan. Return onions to the pan and stir in tomatoes, garlic and basil. Cook and stir about 3 minutes or until tomatoes are tender. Mix in balsamic vinegar and season with salt and pepper. Top chops with the onion and tomato mixture and sprinkle with feta cheese to serve.