Remove the roast from the refrigerator and place on a cutting board at room temperature for 30 minutes. Preheat the oven to 500 degrees. Meanwhile, mix peppercorns, salt, garlic powder, paprika, cayenne pepper, chili powder, onion powder, minced onion, cumin, thyme, and rosemary in a small bowl.
Place the roast in a roasting pan. Drizzle olive oil over the roast and use a brush to spread the oil over all sides of the roast.
Use your hands to press the spice mixture into the roast, spreading it evenly on all sides.
Place the roast in the oven for 15 minutes to sear the outside. The spices should become dark in color.
Turn the oven down to 300 degrees and cook for another 20 to 30 minutes, until the internal temperature of the roast reaches 125 degrees. If you’re using a bone-in rib roast, you may need to add between 10 to 20 minutes of cooking time.
Remove the roast from the oven and let stand for about 10 minutes before slicing and enjoying.