Sprinkle the cubed pork generously with salt and pepper. In a large pan or Dutch oven over medium heat, saute bacon, kielbasa and pork until browned, 10 to 15 minutes. Remove bacon, pork and kielbasa from pan and set aside. Reserve the rendered fat.
Add onions to the same pan and saute until translucent, about 5 minutes. Add prune butter and tomato paste. Mix in well, then add caraway, marjoram and paprika and saute for another minute.
Return the meat to the pan, then add the sauerkraut, broth, carrot, potato and mushrooms. Heat over medium heat until the stew begins to bubble. Cover the pan, then transfer to the oven and bake until the vegetables and meat are fork-tender, 1 to 2 hours. Season to taste.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.