Preheat oven to 450°. Rub steak with oil; generously season with salt and pepper.
Preheat a large ovenproof skillet, preferably cast-iron, over high heat until hot and a drop of water immediately sizzles and evaporates. Sear steak until a deeply golden crust forms and steak begins to pull away, 3 to 4 minutes. Turn steak, then immediately transfer to oven.
Roast until an instant-read thermometer inserted into thickest part of steak registers 125° for rare, 135° for medium-rare, and 145° for medium, 8 to 10 minutes.
Let steak rest 10 minutes, then slice against the grain.
Place a rack closest to broiler; turn on broiler. On a baking sheet, rub steak with oil; generously season with salt and pepper.
Broil steak, turning halfway through, until an instant-read thermometer inserted into thickest part of steak registers 125° for rare, 135° for medium-rare, and 145° for medium, 10 to 12 minutes.
Let steak rest 10 minutes, then slice against the grain.
