1-First: remove the filet mignons from the fridge 30 to 60 minutes before cooking, unwrap them, season generously with salt and ground black pepper, and let them rest at room temperature for even results.

2-Next: preheat the oven to 360°F (182°C) and heat a medium cast iron skillet over high heat for 3 to 5 minutes to get that perfect sear.

3-Then: add 1 tablespoon of neutral cooking oil to the hot skillet and sear the steaks without moving them for 2 to 3 minutes per side go for 1 to 2 minutes per side if using petite cuts until a brown crust forms and the meat releases easily. After that, take the skillet off the heat, add 2 tablespoons of unsalted butter, 5 peeled garlic cloves, and 4 sprigs fresh rosemary, then baste the steaks in the melted butter for added flavor.

4-Transfer the skillet to the oven and roast based on your preference: 2 minutes for rare, 3 to 4 minutes for medium-rare, 5 minutes for medium, 6 to 7 minutes for medium-well, or 8 minutes for well done. Remove the steaks when the internal temperature is 5 to 10°F (3 to 6°C) below your desired doneness, then transfer them to a plate, loosely tent with foil, and rest for 5 to 10 minutes before serving to let the juices settle.

5-Finally, serve with the garlic, rosemary, and butter from the pan for extra taste.