Place two 2-inch-thick porterhouse steaks on a heavy rimmed baking sheet. Brush both sides with a full-flavored olive oil, then rub 1 1/2 tablespoons of the Coriander-Herb Spice Rub into each side of each steak.
Preheat the oven to 450°F. Roast steaks until a meat thermometer inserted into the center registers 125°F for rare, about 25 minutes. Transfer the steaks to a cutting board, cover loosely with foil, and let rest 10 minutes. To serve, cut the 2 whole pieces of meat (known as the loin and the fillet) from each steak, and slice. Give each guest a few slices of the loin and the fillet.