Cooking a turkey is a crucial part of many holiday celebrations, and getting it right is essential for a successful meal. One of the most important factors to consider when cooking a turkey is the cooking time. The general rule of thumb is to cook a turkey for 13 minutes per pound for an unstuffed turkey and 15 minutes per pound for a stuffed turkey. So, for a 20 lb turkey, the cooking time would be approximately 4 hours and 40 minutes for an unstuffed turkey and 5 hours for a stuffed turkey.
It is important to note that these are just general guidelines, and the actual cooking time may vary depending on a number of factors, such as the type of oven you are using, the altitude of your location, and the size and shape of your turkey. It is always best to use a meat thermometer to ensure that the turkey is cooked to the proper internal temperature of 165 degrees Fahrenheit.