Method
Begin by preheating the oven to 350 ºF. Chop the stewed tomatoes coarsely. In a small saucepan, combine the rice vinegar, tomato sauce, stewed tomatoes, and brown sugar. Take a large bowl and crumble the beef in it, then, add half cup of the tomato mixture, breadcrumbs, egg, onion, salt, and pepper, and mix them all together.