For medallions I do a light coat of salt, pepper, flour and high heat with some butter and oil in a cast iron.
Whole backstraps I oil, season and put on a rack in the oven at 175-225 depending on how much time I have. Bake until internal temp is 115-120. Remove and finish on the griddle or grill to your desired temp. I do them to 130*. Rest, slice, Enjoy