Preheat the oven to 450 degrees fahrenheit. Line a rimmed baking dish with foil or parchment paper and place the standing rib roast on it.
If your roast is not trimmed, carefully cut the excess fat off the top to expose the rib bones. Look for the natural separation between the meat and the fat and cut along the separation.
Stand the roast with the rib point up. Insert an oven-safe meat thermometer into the center of the roast, pushing the tip in until it’s directly in the middle.
Combine the mustard, bacon grease, thyme, garlic, and 1 teaspoon of 'Montana Ranch and Cattle Company Steak Seasoning' (or to taste) in a small bowl. Mix well, then rub over the surface of the standing rib roast.
Insert an oven-safe meat thermometer into the center of the roast, pushing the tip in until it’s directly in the middle.
Place the roast in the oven and roast for 20 minutes. Then lower the heat to 350 degrees fahrenheit and continue roasting until the interior temperature reaches 125 degrees fahrenheit.
Remove from the oven and allow the roast to rest for at least 15 minutes before slicing.
Slice, Serve, and enjoy The Greatest Meat on Earth!
Recipe Note
Internal Temperature of Cooked Prime Rib will rise while it rests by 5-7°F (or 3-4°C) every 10 to 15 minutes or so. Take out of the oven just before reaching your desired doneness, as below:
Rare:120°F (49°C). Remove from oven at 115°F (46°C) internal temp.
Medium Rare:125°F (51.7°C). Remove at 48°C / 118°F internal temp.
Medium:130°F (55°C). Remove at 123°F (51°F) internal temp.
Medium Well: 135°F (57°C). Remove at 127°F (53°C) internal temp.
For larger roasts, add 10 minutes extra roasting time for each additional 2 pounds (1 kg). Start checking the internal temperature early, as suggested in the recipe, to be sure. Every oven is different.
