To make this perfect prime rib, start by preparing the meat. Bring the meat to room temperature approximately two hours before you plan to cook it. This is extremely important!
Once you're ready to cook the meat, preheat your oven to 500 F.
Next, prepare the meat by rubbing sea salt all over the prime rib. Then, set it aside while you prepare the marinade.
Make the marinade by mixing together the olive oil, mashed garlic, chopped rosemary, chopped thyme, onion powder, black pepper and another generous pinch of salt in a small bowl.
Mix the marinade together, then rub it all over the prime rib.
Place the prime rib into a cast iron skillet (note: you do NOT need to preheat the skillet beforehand!) and place it in the oven to cook for 20 minutes.
Once the 20 minutes are up, remove the prime rib from the oven, and reduce the oven temperature to 325 F.
Then, insert a meat thermometer, placing the pointy tip of the thermometer into the top of the prime rib, pushing it down into the center of the prime rib. If you aren't using a meat thermometer, see my notes below for the optimal cook time!
For a medium rare cook, allow the meat to cook until it reaches an internal temperature of 135 F - this took approximately 1.5 hours.
Once it's done, remove it from the oven and use tin foil to create a tent around the prime rib while it cools. The prime rib should take approximately 40 minutes to cool.
Finally, once it's done, slice it and enjoy!