Porterhouse steaks are large steaks made up of two actual steaks in one. Though the serving size noted is for one steak per person, one steak could easily feed two diners desiring a smaller portion.
Heat the gas or charcoal grill to high (450-500 degrees). Brush and oil the grilling grate.
Place the porterhouse steaks on the hot grill and allow to sear for 2 ½ minutes. NOTE: for medium doneness steaks increase the time interval to 3 minutes for each segment.
Flip the steak with tongs and sear another 2 1/2 minutes. Rotate 45 degrees and grill a final 2 ½ minutes. Check the temperature with an instant read thermometer.
Start with steaks close to room temperature. Remove them from the refridgerator 2 hours before grilling.