1.To make herb mash, boil or steam potatoes until tender. Mash potatoes with butter, milk and salt and pepper to taste. Stir in herbs; cover to keep warm.
2.Meanwhile, heat a large, non-stick frying pan. Brush steaks with oil, cook until browned on both sides and cooked as desired. Remove from pan; cover to keep warm.
3.Remove excess oil from pan, add butter and shallots. Stir over heat until soft. Stir in wine and vinegar; bring to the boil.
4.Add stock and worcestershire sauce to pan. Stir over heat until mixture boils and thickens.
5.Serve steaks with red wine sauce and herb mash.