Using a paring knife, clean and trim all silverback from the tenderloin.
Using a chef's knife cut away the point, or thin part of the loin. (I reserve this piece for anyone who wants a well done piece of meat or julienne it later to make a kick-ass gourmet cheesesteak).
Cut the remaining loin into steaks approximately 1 and 1/2 inches thick.
Arrange the steaks on a plate and return to refrigerator.
Separate the rosemary leaves from the sprigs.
Using a chef's knife cut the rosemary into 1/4 inch pieces.
Combine the rosemary with 4 tablespoons of kosher salt in a ramekin, and cover with plastic. Shake for one minute to combine.
Remove steaks from fridge.
Pat steaks dry with a clean paper towel.
Generously season one side of the steaks with the rosemary-salt and some freshly ground black pepper.
Repeat steps 9 and 10 for the other side.
To prepare on grill:
Preheat grill to highest possible temperature. Lower to temp to high. place steaks on grill and cook for 6 minutes on one side. Using tongs, turn steaks and cook for 5 minutes on other side for medium rare. Remove steaks from heat and allow to rest 4 minutes. Slice each steak and arrange the pieces in an overlapping manner. Sprinkle with fleur-de-sel and serve with desired sides.
To prepare on stove.
Heat a dry fry pan over high heat for 5 minutes. Add 2 tablespoons olive oil to pan. Follow directions above.