When cooking two roasts at the same time do you add their weight together to determine time?

When cooking multiple roasts at the same time, you should not add their weights together to determine the total cooking time. The cooking time for a roast depends on several factors, including the size and shape of the roast, the type of meat, and the desired doneness.

Cooking multiple roasts at the same time can affect the cooking time of each roast. The roasts may not cook evenly if they are different sizes or shapes. Additionally, the roasts may compete for space in the oven, which can affect the airflow and heat distribution.

To ensure that each roast is cooked properly, it is best to cook them separately. This will allow you to control the cooking time and temperature for each roast individually. You can use a meat thermometer to check the internal temperature of the roasts to ensure that they are cooked to your desired doneness.