Take the steak out of the fridge and let it come to room temperature for about 30 minutes.
Preheat your grill or skillet over high heat.
Pat the steak dry with paper towels to ensure a good sear.
Season both sides generously with salt and black pepper.
Add olive oil to the pan or grill.
Place the steak on the grill or skillet and let it sear without moving it for 4-5 minutes.
Flip the steak and add crushed garlic and rosemary to the pan.
Cook for another 4-5 minutes, adjusting the time for desired doneness.
If using, add butter to the pan for extra flavor during the last minute of cooking.
Remove the steak from the heat and let it rest for 5 minutes before slicing.