Ingredients

For the Roast:

• 4-8 lb. beef bone in rib roast
• 2 Tablespoons coarse Kosher salt
• 2 teaspoons garlic powder
• 2 teaspoons black pepper

For the Horseradish Cream:

• 3/4 cups heavy cream
• 1/4 cup mayonnaise
• 1/2 cup sour cream
• 4 Tablespoons prepared horseradish
• *Salt, to taste
• 1/4 cup chopped chives

Notes:

I use a store-bought horseradish puree, which usually also has some oil and vinegar added to it. Grated horseradish root should be the first ingredient.

cooking

1. The night before you plan to cook the roast, remove it from the packaging. Make a note of how many pounds the roast is before throwing away the package. You'll need that later! Set the roast on a plate and allow it to rest uncovered in the fridge overnight.
2. Two hours before you're ready to cook the meat, remove it from the fridge. Mix together the salt, garlic powder, and black pepper, and rub it all over the roast. It's okay if it doesn't stick to the fatty bits very well. Allow the roast to rest at room temperature for two hours.
3. About 30 minutes before you're ready to bake, preheat the oven to 500 degrees. Grab the note that lists the weight of your roast. Take the number of pounds and multiply it by 5. This is how long you'll cook your roast. For example, if you have a 5 lb. roast, you'll multiply 5 x 5, and bake your roast for 25 minutes.
4. Place your seasoned roast in a roasting pan, fat side up. You can use a roasting rack, or let the ribs act as their own natural rack. Place the roast in the preheated oven uncovered. Bake for whatever amount of time the weight determines.
5. After the allotted time, turn the oven off, set the timer for two hours, and WALK AWAY. Seriously, that's it. The hardest part is simply not opening the oven door for the entire two hours. Tape it shut if you have to--just don't open that door!
6. Allow your roast to continue cooking for the next two hours. After two hours, you can open the oven door to check the temperature of the meat. 120-125 in the center is rare. 130-135 is medium rare, which is my preferred temp for prime rib roast. If the roast has reached 130 degrees, go ahead and take it out of the oven. If it's not quite to temp yet, you can turn the oven back on to 375 and continue to cook until it reaches the desired temp.
7. Remove the roast from the oven, tent with foil, and allow it to rest for 15 minutes before carving and serving.
8. While the roast cooks, you can prepare the horseradish sauce. Combine the heavy cream, mayonnaise, sour cream, horseradish and chives. Season to taste with salt. Refrigerate until ready to serve.