Sauerkraut and Apples - With pork

12 ounces beer 6 tablespoons unsalted butter (3/4 stick) or 6 tablespoons olive oil 4 slices bacon , uncooked and cut into 1/2 -inch-wide pieces 1 small onion[...]

1 quart sauerkraut 1/2 cup onion , thinly sliced 4 slices lean bacon 2 cups apples , sliced 1 1/2 cups white wine 1/2 cup beef stock 1 tablespoon brown sugar[...]