Sear the steak on the grill or in a ripping hot cast iron pan for 1 - 2 minutes per side until desired crust is reached and the internal temperature has increased to 125 - 130 degrees. Once internal temperature is met, pull the steak, add a few pats of butter to the top, and let rest until carryover cooking brings it a medium-rare temperature of 130 - 135 degrees.