Heat the oven to 400°F. Line a large roasting pan with aluminum foil. Place the ribs into the pan and cover.
Bake for 45 minutes. Uncover the pan and pour off any fat.
Heat the oil in a 2-quart saucepan over medium heat. Add the onion and cook until it's tender. Stir in the soup, brown sugar, vinegar and hot pepper sauce and heat to a boil. Reduce the heat to low and cook for 5 minutes or until the sauce is slightly thickened.
Pour the soup mixture over the ribs.
Bake, uncovered, for 30 minutes or until the ribs are fork-tender. Cut the ribs into serving-sized pieces. Return the ribs to the pan and toss to coat with the sauce.
Recipe Note: The sauce mixture can be prepared while the ribs are baking.