Expert: Chef Glen L. Davis II - 12/17/2008

Question
I have prepared a standing rib roast several times. I am now responsible for preparing standing rib roast for about 100 people. I have 2 ovens.  Can I roast several roasts in each oven or do I need to get some other volunteers?  I read about when cooking 2 roasts, increasing the cooking time for one of them by about 20% . Can I do a similar thing in this case?

Answer
First let me tell you, from my experience, if you think you have enough help for a challenging menu, add 2-5 more people!
As far as roasting in the ovens, if they are standard household ovens, you will probably only be able to fit 2 in each MAX. You need to be certain that you are not "crowding" the oven. If you have to much in the oven your cooking time increases exponentially. If you have commercial size ovens (ones that fir full sized sheet pans) you can probably fit 4 roasts per oven.

As far as cooking time I always let the internal temperature of the roast tell me when it's done. Using an instant-read heat resistant thermometer, that can be left in the roast. For medium-rare I like to cook to about 125F (because the roast will increase in temperature by about 15F). For medium I pull the roast out at roughly 130-138F, medium well about 145F, and if you want it well, just cook chicken!

Being that you have cooked rib roast before, I will not "beat a dead horse" and tell you how to properly prepare it.

I hope this helps, please let me know if anything is unclear or if I can be of further assistance. Good luck, you are taking on a difficult task that should not be taken lightly. It will be challenging, but have your logistics planned ahead of time, come up with a back-up plan and you will do just fine!