In a medium saucepan heat oil over medium heat. Add onion and garlic; cook about 4 minutes or until tender, stirring occasionally. Add ale. In a medium bowl stir together apple juice, cornstarch, 3 tablespoons mustard, caraway seeds, rosemary, and pepper; stir into ale mixture. Cook and stir until thickened and bubbly. Cool for 10 minutes.
Meanwhile, in a large saucepan cook potatoes and carrots, covered, in enough boiling, lightly salted water to cover about 10 minutes or until slightly tender but still firm. Drain.
Preheat oven to 350 degrees F. In an ungreased 3-quart rectangular baking dish layer pork chop pieces, kielbasa pieces, potato mixture, apples, and sauerkraut. Pour ale mixture evenly over layers in baking dish.
Bake, covered, for 45 to 60 minutes or until potatoes are tender and center is heated through. If desired, serve with additional mustard.