I'm doing a Christmas party for my wife's office next Friday - 70 people. They have switched from Tri-tip which I am very comfortable with, to Prime Rib, which I have not done before. I've read a bunch of the prime rib posts. Looks like I will be searing them at 500 deg. then cookshack @ 225 till meat reaches 115, then turn down to 140 till done. Does this seem about right?
I have a couple other questions.
Not knowing the preferences of the group as far as meat done-ness. I presume that those prefering rare/medium rare will "tolerate" medium, but those prefering medium may balk at seeing pink. I know this will take the meat past most of our preferences but I think I need to err on the done side for this size group.
What temp should I be shooting for?
Should I take it a little higher before decreasing to the resting temp?
Should I plan on a little higher final temp than 140 deg. to reach this "happy medium"?
Also, Costco was the third place I have checked for prime rib, and they pointed me to the rib roasts that I was standing right if front of that were clearly marked "USDA Choice". Are true prime rib roasts available, or is this what I'm supposed to settle for?
Will there be that much difference in the two grades if done with this cooking method?
Sorry for so many questions, but I'm a little uneasy doing a "first timer" for this size group. I am not able to get a practice run in this week. Thanks for any help and suggestions.