Confession time - I found this recipe in one of my favorite cookbooks, Pillsbury Complete Cookbook. And I went out and spent an exorbitant amount on a piece of meat, but I had read it wrong, so I had the butcher cut it wrong. I ruined it!! I was not to be defeated, though, so this Easter when they went on sale everywhere, I bought a small one and re-did it. I'd have to say it's foolproof, if you just leave it whole, lol!
Heat oven to 325*F. Place roast, fat side up, on rack in shallow roasting pan. Insert meat thermometer so bulb reaches center of thickest part of meat, but does not rest in fat or on bone.
Bake at 325*F for 2-1/4 to 3-1/4 hours, or until meat thermometer registers desired temperature of 140*F for rare, 160*F for medium or 170*F for well done.
For ease in carving, let roast stand covered 10 - 15 minutes. To carve roast, slice from outside toward rib bone and then cut along bone to remove slice of meat. If desired, season to taste with salt and pepper.