In a 3 ½ to 4 ½ quart slow cooker, combine all ingredients, except noodles and sour cream. Cover and cook on low for 6 to 8 hours or until meat is very tender.
Before serving time, cook noodles until done, drain and toss with 2 tablespoons butter or margarine.
While noodles are cooking, stir in sour cream to meat mixture and mix until combined. Adjust with salt and pepper to taste. Serve meat mixture over hot buttered noodles.