COOK steaks in butter in large skillet on medium heat 5 minutes on each side or until cooked through. Remove from skillet; cover to keep warm.
ADD cream, milk, flour and thyme to skillet; stir until well blended. Cook on medium-high heat until mixture comes to boil, stirring constantly. Reduce heat to medium-low; simmer 1 minute, stirring occasionally.
STIR in steak sauce. Serve over steaks.