LPT: Start thawing a large turkey today for Thanksgiving (USA)
Retired butcher here. Turkey thaws at a rate of 3-4 lbs a day (edit: thaw in the fridge, bottom shelf, on a cookie sheet), so a 21 lb bird needs to start thawing now to be ready for Thanksgiving. Note- drips from the turkey can contaminate food below.
Other turkey tips:
* Don't stuff a bird for best results. Stuffing stops the air in the cavity from cooking the bird and makes it so the outside must be overcooked to get the inside to a safe temperature.
* A safer alternative to stuffing that still enhances its flavor: butterfly the turkey and cook it on a bed of stuffing. This will reduce cooking time, look at a few recipes to get a feel for how long it takes.
* If you have to thaw a turkey quickly, keeping it in cold running water for a few hours will work. However, this method take more work, can add another unknown time element if done the day of, wastes water, and I don't think the end results are a good as a slow thaw.
* Avoid recipes that cook at 350°F or higher for the duration. I cook my 18-22lb bird at 250°F for about 3 hours, then go up 400°F for about an hour. (Edit: apparently Alton Brown's method starts high, then goes low, so there are other ways)
* Use a probe meat thermometer to tell if the turkey is done. White meat should be be 165°F (maximum, after resting, the bird will continue to cook, so pull it ~10°F earlier) ~~and dark meat 180°F.~~. Apparently 170-175 for dark meat is recommended by Cook's Illustrated.
* While there are minor differences between brands, almost all frozen turkeys are the same. I always get the cheaper store brands. The only real differences are between Kosher/organic/seasoned. * (edit) Don't baste or open the door to peek- it's more important to maintain a constant temperature. With a higher temp near the end, the bird will brown very nicely.
Swing by /r/meat or PM me if you have questiions. I hope all your birds come out well.
Edit: Front page @_@. RIP my inbox. Thanks to all those who set me straight on the temps.