Heat butter in a 9 or 10 inch non stick skillet. Add beaten eggs and let cook on medium heat just until beginning to set. With a heatproof rubber spatula push cooked ends into center and allow uncooked liquid to flow onto area you pushed egg from. When all of the egg seems to be becoming set add cheese and cooked steak in center. Cover skillet, turn heat to low just to melt cheese, about 30 45 seconds..