Make the meat filling next. Combine the beef, pork, onion, egg, rice, mustard, Worcestershire, salt, garlic powder and paprika in a bowl. Use clean hands to mix it all together well. Then make the sweet and sour sauce. Combine the crushed tomatoes, chicken stock, apple cider vinegar, dark brown sugar, garlic powder and salt in a bowl. Stir it all together well into a gorgeous sauce. Pre-heat the oven to 350 and get out a 9 x 13 baking dish. Spoon about 1/4 of the sauce into the bottom of the dish as the base.