Prepare the cabbage: Bring a large pot of salted water to a boil. Carefully remove the cabbage leaves one at a time and blanch them for 2–3 minutes until softened. Drain and cool.
Make the filling: Heat the oil in a skillet and cook the onion until soft. Add garlic and paprika, then remove from heat.
In a large bowl, combine ground pork, uncooked rice, onion mixture, salt, pepper, and caraway seeds. Mix until well combined.
Fill the cabbage: Place about 2 tablespoons of filling in the center of each cabbage leaf. Fold the sides inward and roll tightly.
Build the pot: Spread half of the sauerkraut across the bottom of a large pot. Arrange the cabbage rolls seam-side down over the sauerkraut.
Add the sliced smoked sausage, remaining sauerkraut, crushed tomatoes, and bay leaves.
Pour in the broth until the rolls are almost covered.
Cook: Cover and simmer gently over low heat for 1½–2 hours, until the cabbage is tender and the filling is fully cooked.
Carefully remove the rolls and adjust the seasoning of the sauce.
Serve: Spoon sauerkraut and sauce onto each plate, place the cabbage rolls on top, and serve generously with sour cream.
