Remove filet mignon from refrigerator 30 minutes before cooking, to bring to room temperature.
Pre-heat cast iron skillet over high heat for 3-5 minutes. Meanwhile, season both sides of the fillet with salt and pepper.
Once the pan is hot, add oil. Reduce heat to medium-high and add steaks into pan, making sure they do not touch each other.
Sear both sides. (For 1" steak, sear for 3 minutes. Turn and sear for another 3 minutes).
If your steak is thicker than 1 inch and/or you'd like a medium to medium-well done steak: transfer the caste iron pan to the oven. Bake until desired doneness (approximately another 5-8 minutes) Use a meat thermometer and refer to the temperature in the notes below.
Once cooked to desired temperature, remove immediately from the hot pan and transfer to a plate. Let rest, covered loosely with foil for 3-5 minutes.
Shrimp
Season shrimp with salt and pepper. In a skillet over medium heat, add 1 tablespoon of butter. Once butter is melted and hot, add the shrimp and spread into a single layer. Cook for about 2 minutes, then turn using thongs.
Add minced garlic to pan and continue to cook shrimp for another 1-2 minutes. Cooked shrimp will form a "U" shape and turn pink in color.
Remove from heat and add remaining tablespoon of butter and parsley.
Pour shrimp and garlic butter sauce over filet mignon and serve immediately. Enjoy!
Notes
Temperature for steakRare: 125 degrees F.Medium-Rare: 135-140 degrees F.Medium-Well: 145- 150 degrees F.Well Done: 160 degrees F