Slow Roasted Prime Rib

5 from 3 votes

Easy slow roasted prime rib roast recipe, cooked to perfection for a tender, juicy, and flavorful meal. Ideal for holidays or special occasions!

Prep Time10

Cook Time2

Rest Before3

Total Time5 10

Course: Main Course

Cuisine: American

Servings: people

Author: Katie G.

Remove rib roast from packaging and place it, bones down, in a roasting pan. Season it on all sides with salt, cover it loosely with plastic wrap, and allow it to come to room temperature for 2+ hours.
Preheat the oven to 500 ℉. Pat the roast down with paper towels.
Combine softened butter, olive oil, garlic, 1 teaspoon salt, pepper, thyme, and rosemary in a small bowl, mixing until well blended. Remove plastic wrap and spread the mixture evenly over the entire roast.
Roast the prime rib in the preheated oven for 15 minutes, then reduce the oven temperature to 325 ℉ and continue roasting until desired level of doneness.
Use a meat thermometer to check the temperature of the meat:
Rare: 120 degrees ℉ (about 15-17 minutes/pound)
Medium Rare: 130 degrees F (about 17-20 minutes/pound)
Medium: 140 degrees F (about 20-23 minutes/pound)
Medium Well: 150 degrees F (about 23-25 minutes/pound)
Note: The beef will continue to cook as it rests out of the oven, so remove it from the oven 5-10 degrees before it reaches your optimal temperature.
Rest: Remove it from the oven and tent it with foil. Allow it to rest for 30 minutes before carving.
Carve prime rib roast by slicing against the grain into about ½ inch thick slices. Serve with au jus and horseradish, if desired.

Bring roast to room temperate before roasting (2+ hours)
Always use a meat thermometer to check for precise internal temperatures.
Remove the roast about 5-10°F below your target temperature, as it will rise while resting.
Let the roast rest for 15-20 minutes before carving for maximum juiciness.
Store in an airtight container in the fridge for 3–4 days.