Into your slow cooker add the stew beef, mushrooms, onion soup mix, garlic, tomato paste, worcestershire sauce and beef stock.

Stir.

Cover and cook on low for 6 hours or high for 4.

30 minutes before serving add your noodles to the slow cooker and stir.

Cover and cook until the noodles are al dente.

Into a small bowl whisk together the sour cream and flour.

Add 1 cup of the liquid from the soup to the sour cream mixture and whisk until smooth.

Stir the sour cream mixture into the slow cooker and let cook another 10 minutes.

Serve!