• Generously season steaks all over with salt and pepper.
• If desired, set steaks on a wire rack; set in a rimmed baking sheet and refrigerate, uncovered, overnight to dry out the exterior.
• Otherwise, proceed with the next step.

If cooking in the oven:

• Arrange stakes on a wire sitting in a rimmed baking sheet.
• Pre-heat the oven to anywhere between 200°F and 275°F; if the oven goes lower, you can set it to an even lower temperature, although it will take longer to cook.
• Place steaks in the pre-heated oven and cook until an instant-read thermometer registers 105°F for rare, 115°F for medium-rare, 125°F for medium or 135°F for medium-well.
• This will take about 20 minutes for rare steaks and up to about 40 minutes for medium-well; cooking time can vary dramatically depending on many factors, so check often.
• Just before steaks come out of the oven, add 1 tablespoon oil to a cast iron, carbon steel or heavy stainless steel skillet; heat over high heat until smoking.
• Add steaks and butter to skillet; cook until each side is well browned; about 45 seconds per side.
• Using tongs, hold steaks sideways to sear edges.
• Serve right away; there's no need to let reverse-seared steaks rest.

If cooking on the grill:

• Light one chimney full of charcoal.
• When all the charcoal is lit and covered with gray ash, pour out and spread the coals evenly over half of coal grate.
• Alternatively, set half the burners of a gas grill to high heat; set cooking grate in place, cover grill and allow to pre-heat for 5 minutes.
• Clean and oil grilling grate.
• Set steaks on cooler side of grill and let cook, uncovered, turning occasionally, until an instant-read thermometer registers 105°F for rare, 115°F for medium-rare, 125°F for medium or 135°F for medium-well.; cooking time can vary greatly, so check the steaks often.
• Transfer steaks to a platter and tent with foil.

For both methods:

• If you are using a charcoal grill and your coals have died down, build up the biggest fire you can; if using a gas grill, make sure all burners are turned to their highest heat and allow the grill to pre-heat with the lid closed.
• Return steaks to the hottest part of the grill and cook, turning frequently, until crisp and charred all over, about 1-½ minutes total; serve right away.