Preheat oven to 400. Heat oil in a large cast-iron skillet over medium-high until it begins to smoke. Pat steak dry with paper towels. Season each side with 1/2 teaspoon coarse salt and 1 teaspoon cracked pepper.

Cook steak in skillet over medium-high heat until a dark crust has formed, 5 to 7 minutes per side (reduce heat if meat is browning too quickly). Make sure not to turn the steak before the crust has formed.  Hold the steak with tongs and quickly brown the edges before turning over completely. 

Transfer skillet to oven. Roast until an instant-read thermometer inserted in the thickest part of steak registers desired doneness, 5 to 15 minutes. Transfer to a plate. Cover loosely with aluminum foil, and let rest 5 to 10 minutes (temperature will then rise another 5 to 10 degrees). Slice across the grain; serve with your favorite steak sauce. Cover and refrigerate any leftovers, up to 2 days.