Christmas Eve Prime Rib

Every Christmas Eve my family all gets together for a big meal and my grandfather makes an amazing prime rib. This year was our first to be on our own and making the meal for ourselves. We were quite nervous about ruining the roast, but luckily it turned out great and was actually really simple to do, you just need to allow plenty of time for it to cook.

5 pound beef rib roast
2 teaspoons salt
1 teaspoon ground black pepper
1 teaspoon garlic powder

Allow roast to stand at room temperature for at least 1 hour.
Preheat the oven to 375 degrees F. Combine the salt, pepper and garlic powder in a small cup. Place the roast on a rack in a roasting pan so that the fatty side is up and the rib side is on the bottom. Rub the seasoning onto the roast.
Roast for 1 hour in the preheated oven. Turn the oven off and the leave the roast inside. DO NOT open the door. Leave it in for 3 more hours.
30-40 minutes before serving, turn the oven back on at the 375 degrees F to reheat the roast.
The internal temperature should be at least 145 degrees F.
Remove from the oven and let rest for 10 minutes before carving into servings.