With the back of a heavy saucepan, crush the white and black peppercorns.
Remove all fat from the entrecotes. Season with salt and crushed peppercorns.
Heat a large heavy saucepan. Pour in oil, and over high heat, cook the entrecotes 4 minutes on each side (for medium rare). Transfer meat to a warm platter and reserve.
Pour out oil from the pan, deglaze with port, and reduce. Add cream and veal stock and continue to reduce until sauce is thick enough to coat the back of a spoon. Whisk in butter, 1 small piece at a time. Season, to taste, with salt.
Place 1 entrecote on each warmed serving plate. Ladle sauce over steaks and divide remaining peppercorns equally over each portion.