1. Preheat oven to 350 degrees Fahrenheit.
2. Bring the steak to room temperature. Generously season your steak with salt and pepper.
3. Heat up olive oil in a cast-iron skillet, place steak down and sear on both sides till a nice golden crust develops, approximately three to four minutes per side. Add rosemary and garlic halfway through and sear along with the steak.
4. Place steak on a sheet pan. Set the thermometer to 129 degrees Fahrenheit. Insert thermometer inside steak, and place steak in the oven at 350 degrees Fahrenheit.
5. Once the beeper goes off, take steak out and let it rest for 10 minutes.