1.Season beef; cook beef in heated oiled large frying pan. Remove from pan; cover to keep warm.
2.Cook mushrooms in same heated pan, stirring, until tender. Add flour; cook, stirring, for 1 minute. Gradually stir in stock; cook, stirring until gravy boils and thickens.
3.Serve beef with gravy.
Veal T-bone steaks can also be used.Note