1/2 cup plus 3 tablespoons all-purpose flour, divided
Combine 1/2 cup flour with the salt and pepper. Toss with beef to dredge and transfer to slow cooker. Cover with green onions and mushrooms.
Combine beef broth, Worcestershire sauce and ketchup. Pour over beef and vegetables; stir well. Cover and cook on low setting for 8 to 10 hours. One hour before serving, turn to high setting.
Make a paste of wine and 3 tablespoons flour; stir into slow cooker, mixing well. Cover and cook until thickened.
Serve over rice or buttered noodles.