Heat butter in a skillet over medium heat. Add onion and garlic; cook until onion is translucent, about 5 minutes. Stir in potatoes, water, carrots, bouillon, sugar, and caraway seeds; bring to a boil. Reduce heat to simmer for 15 minutes until tender.
STEP 2
Layer sauerkraut on top of vegetables; place sausages on sauerkraut. Cover, and cook until sausages are heated through, about 15 minutes.
STEP 3
Whisk sour cream and flour together in a bowl; stir into sauerkraut mixture. Simmer until thickened; season with salt and black pepper.