A holiday favorite, I know. I've always cooked mine at 425*, usually less than an hour, to an internal temp of 125*, covered with foil and rested for 20-30 minutes, at which time it should reach 135*.
In this month's Fine Cooking though, there is a recipe that calls for cooking the tenderloin at 250* for up to 2 HOURS, at which time it should have reached 130* internal.
Well now that I'm thinking about it, that is how I cook standing rib roast. It produces a more uniformly red color from exterior to interior. But before I try it on a $50 tenderloin, I sure would appreciate someone on this board giving me a jolt of confidence that this is a better way. Takers?