How do I figure the time to roast 4 4-5 lb boneless legs of lamb at the same time?

I'm serving 18-20 people, have a big GE oven with both regular and convection setting, usually use the high-heat method (425) and roast one for about 45 min. Would 4 at once be 4 times that, or less? I'd expect the convection setting, which I've never used, to reduce cooking time, perhaps work well for this.

  • Posted by: SBKSB
  • August 20, 2014


Lisi32 August 21, 2014
I don't know anything about convection - but for a regular oven I agree with above. Same cooking time for one or four roasts. Have a great dinner!
Susan W. August 20, 2014
Oh gosh no, not 4 times as long. It most probably won't take any longer for four as it does one as long as there is space between each one. Definitely use the convection setting. Keep in mind the convection setting will add 25° to the temp, so you may want to cook the roasts at 400°. My mom has a big roomy gas Wolf convection oven and her roasts always come out so beautifully browned. You probably know this, but be sure to give your roasts about an hour of counter time to come to room temperature.
SBKSB August 21, 2014
I once tried cooking 2 beef roasts at the same time, making the assumption that it would take the same time as one, but that turned out not to be true--took nearly 2x as long and messed up dinner--hence my query. Something to do with surface area and heat absorption, perhaps? Convection might help.
Thanks for your input.
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