Let roast stand at room temperature 1 hour.

Prepping: Fill a chimney full of coals 20 minutes before needed. Searing: Make bed of coals with DO on top. Sear roast in olive oil on all sides uncovered. Move DO off coals and cover. Slip a rack under roast to lift it up. Roasting: Push coals to side and re-arrange coals so there are 13 coals in a ring on bottom. Put DO back on coals. Put thermometer prob in center of roast, cover. Put 25 coals on lid around rim. This simulates 425 degrees. Roast at 425 for 20 minutes. Just let coals burn down. Meanwhile start more coals in chimney. After 20 minutes. Replenish coals but now only 21 on top and 11 on bottom. This simulates 350 degrees. Roast at 350 for X minutes or until thermometer inserted into center of meat registers 110°F. Transfer beef to a large platter and let stand, uncovered, 25 minutes. (Meat will continue to cook, reaching about 130°F for medium-rare.) Make gravy: Remove fat from DO so there are about 2 tablespoons left in DO. Add some olive oil if necessary. Sprinkle in 3 tablespoons flour and whisk till smooth. Whisk in beef stock. Simmer for at least 3 minutes until thickness you like. If not thick enough, sprinkle in some Wondra.