1. Preheat your oven to 275 degrees Fahrenheit.
  2. Pull out the Prime Rib from your refrigerator and let sit out within the aluminum container without a lid (reserve lid for later use) for a minimum of 3 hours to come to room temperature.
  3. Place the Prime Rib without a lid into the oven and rotate every 30 minutes, after the first hour, for up to 2 hours.
  4. After the first hour use a thermometer and place it in the thickest part of the rib roast to check internal temperature.
  5. Cook time may go up to two hours for well-done temperature throughout.
  6. If desired internal temperature has not been reached after 2 hours, place prime rib back into the oven at 265 and check temperatures every 15 minutes.
  7. After reaching your desired internal temperature listed below, you will cover the prime rib again with the aluminum lid for 20 minutes to rest outside of the oven. Do not seal the container, only cover.
  8. After the 20 minutes rest time, it is now ready to slice and serve.

Rare at 118 degrees Fahrenheit on thermometer
Medium Rare at 125 degrees Fahrenheit on thermometer
Medium at 135 degrees Fahrenheit on thermometer
Medium Well 145 degrees Fahrenheit on thermometer
Well Done 155 degrees Fahrenheit on thermometer

For the Au Jus just place liquid in a pot and warm before serving. The horseradish cream is to be served cold.