If it's roast beef and you want it medium rare in the middle and cooked on the ends then put the oven up to 400 degrees for 20 - 30 minutes and then put it down to 330 - 350 (basting every 15 minutes in it's own juices. It would 15 - 20 minutes per pound. Frozen beef roasts cook faster so cook 12 - 15 minutes per pound.You can use a thermometer to test it or, cut into the middle of the roast a little to see if it's the way you want it.ow long is the cooking time for a 9 pound ham at 25 minutes per pound? I would say about 3 hours and 45 minutes. add 5 minutes if you want it well done, and subtract 5 if you don't want it as well done. Also use a meat thermometer to insure the h … am is cooked right.