1 5-6 pound tenderloin, trimmed
3 tbsp. dijon mustard
1 tbsp. dried sage
1 1/2 tbsp. green peppercorns, drained
1 1/2 tbsp. whole black peppercorns, ground and divided
1 1/2 tbsp. whole white peppercorns, ground and divided
1 tbsp. butter, softened
Recipe
Cut tenderloin lengthwise to within 1/2" of 1 long edge, leaving edge intact. Open tenderloin out flat. Place heavy-duty plastic wrap on tenderloin; pound meat to flatten slightly. Remove wrap; spread meat with mustard. Sprinkle sage, green peppercorns and 1/2 tbsp. each of black and white ground peppercorns over mustard.
Fold one side of tenderloin back over and tie securely at 3 " intervals with heavy string. Spread butter over ouside of tenderloin and sprinkle with remaining ground peppercorns.
Place tenderloin on a rack in a roasting pan; insert meat thermometer into thickest part of tenderloin.
Bake at 425 degrees for 45 minutes or until thermometer registers 145 degrees (med. rare) or 160 degrees (medium). Let stand 10 minutes before slicing.