Take the filet mignon out of the refrigerator about 30 minutes before you cook it so the steaks get closer to room temperature.
Pat each steak completely dry with paper towels and brush both sides with olive oil.
Generously season both sides of each steak with salt and black pepper.
Preheat your oven to 500°F and put an oven-safe ceramic plate on the bottom rack to get it super hot—it’ll give you that sizzle that Ruth’s Chris is famous for!
Heat a cast iron skillet over high heat until it is just about smoking, then sear each filet for 2 minutes per side until a brown crust forms.
Transfer the skillet to the oven for about 5–6 minutes for medium-rare, or longer if you prefer your steak more done.
Remove the steaks from the oven, top each one with a tablespoon of butter, and let them rest for 5 minutes on the heated plate.
Sprinkle with chopped fresh parsley before serving.