I have a piece of beef tenderloin - maybe 1-1/2 to 2 lbs - that I'm planning to cook on my gas grill tomorrow. I'll probably just season it with salt, pepper, rosemary, not sure what else, and grill it over indirect heat until done to med. rare, then slice. Just wondering whether I should serve it with some kind of sauce, I happen to have a couple of rolls of scape butter in the freezer - how about if I do something with that? Or should I make a mushroom-red wine sauce? This is casual, outdoor dining, by the way, not fancy tablecloth and crystal.