Answer:
Dang now you made me hungry.... anyways here's your answer lol:
1. Preheat oven to 500 degrees.
2. Add the butter to a cast iron skillet on high heat.
3. Add the Kosher salt and black pepper to the steaks and add to the pan.
4. Sear the steaks on high heat for 30 seconds on each side.
5. Add the rosemary sprigs to the top of the steaks and spoon over the butter onto the steaks.
6. Put the pan with the steaks into the oven for 4-5 minutes (if you'd like you can flip them halfway through - I don't and you can see how mine have cooked through.)
7. Rest for five minutes before serving.
Have a nice day and stay safe :)
Explanation: