For the chateaubriand, mix well butter, parsley, chives, garlic and salt. Form into a roll with wet hands, wrap in plastic wrap and freeze.
Coat the meat with oil, roast on the grill for 4 to 8 minutes. To serve, season the meat with salt and pepper.
Place a piece of the herb butter on top and serve the Chateaubriand sprinkled with cress.