By Emily ParkerUpdated November 2026
Learning how to cook filet mignon on cast iron skillet gives you a steak with a deep brown crust and a rosy, tender center in about 10 minutes of active cooking. The method relies on heat retention rather than fancy equipment, so a well-seasoned pan does most of the work. This guide walks through selection, preparation, searing and resting.
Choose and Prep the Steak
Filet mignon is cut from the tenderloin and is naturally lean, so it benefits from a bit of fat and a generous seasoning. Look for steaks about 1.5 inches thick, since thinner cuts overcook before they develop a crust. Pat the steak dry with paper towels, season both sides with coarse kosher salt and black pepper, and let it sit at room temperature for 30 to 45 minutes. Dry surfaces brown faster, and a room-temperature center cooks more evenly.
Shopping for one? See our guide: 7 Best Cast Iron Skillet Pan Sets for Home Cooks (2026).
Sear in the Cast Iron Skillet
Preheat a 10- or 12-inch cast iron skillet over medium-high heat for about 5 minutes, until a drop of water skitters across the surface. Add a teaspoon of high-smoke-point oil such as avocado or canola, not olive oil. Lay the steak away from you so you don’t splash hot oil, then leave it alone for 3 to 4 minutes. Flip once, and sear the second side for another 3 minutes.
Add Butter and Aromatics
Reduce the heat to medium, add 2 tablespoons of unsalted butter, 2 smashed garlic cloves and a sprig of thyme or rosemary. Tilt the pan and spoon the foaming butter over the steak for about 1 minute. This basting adds flavor and helps the crust develop evenly.
Check Doneness and Rest the Steak
Use an instant-read thermometer inserted from the side. Pull the steak at 125°F for rare, 130°F for medium-rare and 140°F for medium, since carryover heat raises the internal temperature by about 5 degrees while it rests. Transfer the steak to a cutting board and rest it for 5 to 8 minutes, loosely tented with foil. Resting lets the juices redistribute so they stay in the meat rather than running onto the board.
| Doneness | Pull Temperature | Final Temperature After Rest |
|---|---|---|
| Rare | 125°F | about 130°F |
| Medium-rare | 130°F | about 135°F |
| Medium | 135°F | about 140°F |
Common Mistakes to Avoid
- Starting with a cold pan, which steams the steak instead of searing it.
- Crowding the pan, which drops the surface temperature and prevents browning.
- Moving the steak constantly, which slows crust formation.
- Cutting into the steak immediately, which lets juices escape.
- Using butter from the start at high heat, where it can burn before the sear is done.
Recommended Gear
- Lodge Cast Iron Skillet: a widely available, heavy pan that holds heat well for a hard sear. View on Amazon
- ThermoPro Instant-Read Thermometer: a fast digital probe that makes checking doneness simple. View on Amazon
If you’re still building your pan collection, the guide to Cast Iron Skillet Size Guide: How to Pick the Right Diameter (2026) helps you match pan size to your cooktop and portions. For keeping the seasoning intact after a buttery steak night, see How to Clean a Cast Iron Skillet: 5 Steps That Protect the Seasoning.
FAQ
Do I need to oil the steak or the pan?
Lightly oil the pan, not the steak, since oil on the surface can make the seasoning fall off. A thin coat of high-smoke-point oil in the hot skillet is enough for the sear.
Can I cook filet mignon in a cast iron skillet without a thermometer?
You can, but it takes practice. Touch the steak’s center with your fingertip and compare the firmness to the base of your thumb for medium-rare, though a thermometer is far more reliable.
Should I finish the steak in the oven?
For steaks thicker than 1.5 inches, finishing in a 400°F oven for 3 to 5 minutes after searing helps the center reach temperature without overbrowning the crust. Most filets at this thickness can be finished entirely on the stovetop.
Conclusion
A hot, well-prepared cast iron skillet gives filet mignon a crust and center that rival a steakhouse. Dry the steak, sear it hard, baste with butter and rest it before slicing. With a reliable thermometer, you can repeat the result every time.
Related reading
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About Emily Parker
Emily Parker is part of our editorial team and reviews and edits our cookware & knives guides, checking product details against manufacturer specifications and owner feedback.
