Place chunks of pork in a large ziplock bag.
Add flour, paprika and salt to the bag. Seal bag and toss chunks of pork in the flour mixture until meat is coated. Set aside.
Heat oil in a large heavy bottom deep pan, such as a dutch oven, over medium heat.
Add diced onion, and cook stirring occasionally until onions are soft and turn translucent.
Add pork chunks and cook until browned on all sides, stirring occasionally.
Add 2-3 tablespoons water to the pan and stir scraping up the browned bits in the bottom of the pan.
Cover pan and cook over low heat for 1 hour, stirring occasionally. Sauce will thicken as it cooks. Add a little more water if needed.
Drain sauerkraut and rinse with cold water. Pressing out excess water.
Add rinsed sauerkraut to the pan, and stir to combine with the pork.
Pour in 2 cups hot water and stir. Increase heat and bring to a boil, cover pan and simmer on low for another 30-40 minutes, stirring occasionally until the pork is fork tender.
Remove pan from heat.
Place sour cream in a mixing bowl. Add 1½ cups of the hot broth from the pan to the sour cream in the mixing bowl. Whisk together until well combined and creamy.
Stir the sour cream back into the pan and return pan to the heat. Cook overflow heat for 2-3 minutes until heated through, stirring constantly. Do not allow mixture to come to a boil.
Taste and season with additional salt if needed.
Serve in small bowls with slices of freshly baked bread.