You'll need about 6-8lbs - you'll want to have a few leftovers.
You'll also want to tie it with butcher string to keep a nice shape for
presentation.
If you want to stuff it, you take a nice sharp, long knife and
cut an X throught the center lenghtwise, it is easier than it sounds.
You could also butterfly it, stuff it and then tie it.
You can stuff it with jst about anything you want.
Here's a site that if you haven't used it it can be helpful -
you can find a recipe and at the bottom change the serving size.
http://beef.allrecipes.com/recipes/recipe_scale.asp
I've stuffed both beef and pork tenderloins with a mix of
prosciutto, provolone, sauteed onions, mushrooms and celery.
You may also want to do two depending how rare everyone wants it.
Once you decide just what route your going, post back and I'm sure you'll get
some more ideas.
