Pat the hanger steak dry
Trim any excess silver skin or tough membrane
Season generously with salt and black pepper
Let it sit at room temperature for 20 to 30 minutes
Heat a cast-iron skillet or grill over high heat
Add a small amount of high-smoke-point oil
Sear the steak for 3 to 5 minutes per side for medium-rare, depending on thickness
Sear the edges briefly if needed
Check for doneness with a meat thermometer
Remove at 125 to 130°F for medium-rare
Remove at 135 to 140°F for medium
Rest the steak for 5 to 10 minutes
Slice thinly against the grain
Serve immediately