After searing beef, like steaks, I've always used a hot oven to roast it afterward. Most recipes ask you to roast a tenderloin at 400-450 degrees for a few minutes after searing. However, on Bourdain's xmas sepcial, he roasted tenderloin at a low temperature, for a much longer period of time. What do you recommend? I'd try it out, but Tenderloin is a little expensive for experimentation.
Also - spare me the chatter about tenderloin being an inferior cut of beef and all that noise. It's not my favorite, and I'd prefer something else, but it's a family crowd pleaser.