Skillet-to-oven technique – You briefly sear the filet mignon in a hot oven-safe skillet (you may use a cast-iron pan as well) about 2 minutes per side, until a brown crust forms. Then, transfer it to the oven for a few minutes to finish cooking.
To get the best doneness of the meat according to your preference, you need to use a reliable meat thermometer (digital, instant-read ones are ideal). Having a food thermometer in handy will help you monitor how the filet mignon is cooking and will help you achieve the doneness that suits your taste.
For a rare filet mignon, try to aim for an internal temperature of 120°-130°F which is the juiciest stage of cooking.
For a medium-rare filet mignon, you would need to strive for an internal temperature of 130°-135°F. It should have a little bit of resistance when poked with your meat thermometer.
Don’t forget that carryover cooking from resting the meat can increase the internal temperature by 5°F, so you need to know when is the right timing to let the meat rest without cooking it all the way.
Ingredients
Filet mignon steak (1-2 in. thick) (amount depends on the number of people you will serve)
1 tbsp. grapeseed oil or extra virgin olive oil (but if unavailable, any neutral oil)
2 tbsp. unsalted butter
1 clove garlic
2 sprigs fresh rosemary
Kosher salt
Flaky salt, to taste
freshly ground black pepper to taste
Cooking Filet Mignon to Perfection
Let your steak come up to room temperature for about 30 minutes.
Preheat your oven to 415°F.
Pat the steak dry with paper towels and season it with kosher salt.
Melt your unsalted butter with the oil in a cast-iron skillet on your stove over medium-high heat.