Pat the top sirloin steak dry with paper towels
Trim any excess fat if needed
Season generously with salt and black pepper
Let the steak sit at room temperature for 20 to 30 minutes
Preheat a skillet, grill, or broiler over high heat
Add a small amount of oil if using a skillet
Sear the steak for 3 to 5 minutes per side for medium-rare, depending on thickness
Flip only once during cooking
Use a meat thermometer to check doneness
Remove the steak from heat at 130°F to 135°F for medium-rare
Remove the steak from heat at 140°F to 145°F for medium
Rest the steak for 5 to 10 minutes before slicing
Slice against the grain
Serve immediately