Remove steak from fridge and let it sit at room temp for 30 minutes. Pat dry and season with salt and pepper.

Heat a cast iron skillet over medium-high until very hot. Add olive oil and sear steak for 3–4 minutes per side.

Lower heat, add butter and garlic. Baste steak with garlic butter for 1–2 minutes.

Transfer to a plate, cover with foil, and rest 5–10 minutes.

Slice against the grain and garnish with parsley and remaining garlic butter. Add chili flakes or chimichurri if desired.