In a large Dutch oven or heavy-bottomed pot, cook the chopped bacon over medium heat until crispy, about 5-7 minutes. Use a slotted spoon to transfer the bacon to a paper towel-lined plate, leaving the bacon fat in the pot.

Increase the heat to medium-high and add the pork shoulder cubes to the pot in a single layer. Sear until browned on all sides, about 6-8 minutes, then transfer to a plate.

Lower the heat to medium and add the sliced kielbasa, diced onion, and sliced mushrooms to the pot. Sauté until the onions are translucent and the mushrooms have softened, about 5 minutes. Stir in the minced garlic and cook for 30 seconds until fragrant.

Pour in the dry red wine to deglaze the pot, scraping up any browned bits from the bottom with a wooden spoon. Let it simmer for 2 minutes until the liquid reduces slightly.

Return the browned pork and crispy bacon to the pot. Stir in the shredded fresh cabbage, rinsed sauerkraut, beef broth, tomato paste, caraway seeds, dried marjoram, and chopped prunes. Season with the black pepper.

Bring the stew to a boil, then reduce the heat to low. Cover the pot with a tight-fitting lid and let it simmer gently for at least 1.5 to 2 hours, stirring occasionally, until the pork is fork-tender and the flavors have deeply melded.

Taste the stew and adjust the seasoning with salt if needed, keeping in mind the bacon and sausage are already salty. Serve hot in deep bowls alongside thick slices of crusty rye bread to mop up the savory broth.