Combine breadcrumbs and milk in a medium mixing bowl, stirring well; set aside 5 minutes. Add pork, onion, salt, and pepper; mix well. Shape pork mixture into 12 patties.
Melt shortening in a large skillet over medium heat. Brown patties on both sides; drain well. Place patties in a lightly greased 13- x 9- x 2-inch baking dish.
Combine remaining ingredients; stir well. Pour over patties. Cover; bake at 350° for 50 minutes.