Drop bratwurst into boiling water; remove from heat. Let soak 5 minutes. Drain. Melt butter; add bratwurst and cook until golden brown. Add water; reduce heat and simmer, uncovered, 15-20 minutes, turning bratwurst occasionally. Replenish water if cooking water boils away. Put sausages on plate and cover with foil.
With whisk, beat flour and salt into sour cream. Then stir sour cream mixture into liquid in skillet. Cook 5-8 minutes over low heat, stirring constantly. Cut sausages into 1/2 inch rounds; drop into skillet. Simmer to heat through.
