cooking a nice juicy turkey?

Same heat more time

If you have a convection oven, use it. (Im talking about a convection fan in your oven, not a separate unit called a convection oven)

Also, rotate the turkeys every time you baste to assure even cooking (like every 45 minutes or so)

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Contrary to a poster below, the birds WILL take longer to cook. The 2nd turkey will do two things that will cause this.

1) The 2nd bird will have a cooling effect on the oven simply from the volume of an 11lb cold bird.

2) The oven will be more crowded which will slow down the convection of air. The more air movement, the quicker things cook (the very principal of a convection oven).

There are several ways to do it. Most likely, your mother is "old fashioned" and cooking it to 170 or 180 degrees before she removes it. You can Brine it, that works. You can use the bag. Get a big roaster with a lid. The main thing is to baste it every 30 minutes (unless you cook it in the bag... I never have, so I do not know if you can baste it in the bag). Take the turkey out when it reaches 160 in the thickest part of the thigh. The temp will continue to rise in the turkey even after you take it out of the oven. Let is sit for about 20 minutes. Should be good to go...

SAME TIMING SAME HEAT SETTING

you are merely stuffing your oven with more than normal. So you would cook the birds about the same time as you would if you cooked one in one oven and the other in another oven!! You are just saving "fuel" by doing both at the same time.

A bird that weighed 21 or 22 pounds would take longer as it is one piece and more dense than 2 birds half that weight each.

I had my hubby get me a hickory smoked turkey breast to go with the ham and beef roast to set on the "groaning board" for Thanksgiving day. These 3 pieces of meat are all the same size comparatively, except the turkey breast is already cooked and so is the ham. They are heat and eat so the cooking time will be the beef!

The beef roast will go in one oven and the ham and turkey breast will go in another as they don't need the same timing or temperature.

Deep fry it 3.5 minutes per lb. mmmmmmmmm