Step #1 At least 2 1/2 hrs & up to 12 hrs before you plan to grill the steaks, rub them with the mustard & sprinkle with the course salt & black pepper.
Step #2 Wrap the steaks in plasic & put in the fridge.
Step #3 Prepare the sauce, first melting the butter in a small skillet over med-heat/flame.
Step #4 Stir in the rosemary & onion & cook this until the onions are translucent, about 5 mins.
Step #5 Stir in the bourbon, remove the skillet from the heat, & let the mixture cool for 10 mins.
Step #6 Strain the mixture into a small bowl & return it to the skillet.
Step #7 Discard the solids.
Step #8 Add the remaining sauce ingredients to the skillet & cook over medium-low heat for an extra 5 mins.
Step #9 Keep the sauce warm.
Step #10 Remove the steaks from the refrigerator & let them sit at about room temp for about 30 mins.
Step #11 Fire up the grill, grill the steaks to desired doneness.
Step #12 Serve the steaks hot with the rosemary-bourbon sauce.
Enjoy the Strip Steak With Rosemary - Bourbon Sauce recipe