Beef Stroganoff

1 lb hamburger beef
1 packet slow cooker stroganoff seasoning
1 c sliced mushrooms (or cream of mushroom soup)
1 c sour cream
1 cup water (or as directed on seasoning packet)

Combine the beef, stroganoff seasoning, mushrooms, and water in a crockpot. Stir untilt he seasoning is dissolved. Cook on low for 8 hours. Immediately before serving, stir in sour cream. Serve with egg noodles.