In a small bowl, mix together the mustard, olive oil, savory, and thyme.

Trim the meat of all excess fat and silverskin. Cut the filet in half to make two equal pieces about 7 inches long. You'll have one piece with the broad double-pieced butt portion and a thinner piece that tapers to a small tip. Tuck the tapered tip under and tie with twine to fashion two equally thick roasts. Tie each roast at 2-inch intervals.

Heat the oven to 450 degrees F. Heat a heavy-duty roasting pan or large Dutch oven or skillet over medium-high heat. Pour in enough vegetable oil to just cover the bottom of the pan. Pat the filets dry, salt them generously, and lay them in the pan; cook without disturbing them until the bottoms are a rich brown. Turn the beef and sear the other sides. It will take about 4 min. per side (there are three or four sides per roast) to get a good sear.

When the filets are seared, transfer them to a cutting board, brush them with the mustard and herb mix, and then generously grind fresh pepper over them. Put a rack in the roasting pan, lay the meat on the rack, and roast until the internal temperature reaches 115 degrees F for medium rare, about 20 min. (Check after 15 min.; roasting time will vary depending on searing time.) Remove the filets from the oven and let them rest in the warm spot for at least 15 min. before slicing. Serve warm or at room temperature.