Step 1

Season steaks generously on all surfaces with kosher salt and black pepper. Add vegetable oil to 12-inch, heavy-bottomed cast iron or stainless steel skillet. Heat over high heat until oil just begins to smoke. Add steaks to pan, and cook without moving until deep golden-brown crust develops on first side, three to four minutes. Flip steaks over.

Step 2

Add butter, thyme sprigs, and shallots to pan. Turn heat down to medium-high. Continue to cook, occasionally basting steaks by tilting pan towards you and spooning hot fat over surface of steaks. If steaks start to become too dark, turn lower heat. Continue to cook until instant-read thermometer inserted in to center of steak registers 125°F for medium-rare (between three and seven minutes, depending on how powerful your range is). Remove steaks from pan, place on rack set in rimmed baking sheet, pour fat, shallots, and thyme from pan over steaks, tent loosely with aluminum foil, and allow to rest for until center of steak cools to 120°F (about ten minutes). Meanwhile, make pan sauce if desired.