When the onion is slightly browned, pour off almost all of the grease (or all of it if you're watching fat content), Add pork and beans, sugar, vinegar and catsup.
Stir well, season with a pinch of chili powder.
Pour mixture into ceramic bean pot or covered dish.
Bake at 350 degrees one hour or until mixture is cooked down so that it's not too runny. You can also cook this mixture slowly on the stove, careful to stir occasionally so the beans won't burn. They'll cook down.