Step 1

Heat a large heavy-bottomed skillet (preferably cast iron) over high 5 minutes. Generously season steaks with salt and pepper. Add 1/2 teaspoon butter to pan, then immediately top with one steak. Repeat with remaining 1/2 teaspoon butter and steak. Cook without moving steaks until a golden brown crust forms, 3 to 4 minutes. Turn and cook 2 minutes more for rare, or 3 to 4 minutes more for medium-rare. Transfer to a cutting board and let rest 5 minutes. Slice steaks against the grain; serve with sauce, if desired.

Step 2

Heat a 10- or 12-inch cast-iron skillet over high heat. Season the steaks liberally with salt and pepper. Seconds before adding a steak, drop 1/2 teaspoon of the butter into the pan and immediately top with the steak. Repeat with the remaining steak. Sear for 3 minutes without moving the steak (to form a crust). Turn and cook for 2 minutes for rare or 3 to 4 for medium rare. Remove the steaks from the pan and let them rest on a board or platter for a few minutes before serving.