Direction

1. In a small bowl, combine the salt, pepper, rosemary, basil and orange zest. Dab the sirloin dry and rub all over with the steak seasoning then cover with plastic wrap. Allow to marinate for a minimum of 10 minutes, but up to 24 hours.
2. Heat the grill, either charcoal or gas, to medium-high heat and oil grates with cooking spray or vegetable oil. Alternately, you can use a grill pan on an indoor burner.
3. Grill the steak for 3-4 minutes on each side. The total time will depend on your desired level of doneness, but also the thickness of your steak. When in doubt, use a meat thermometer. Pull it off at 140°F for medium rare. Allow the steak for 10 minutes before cutting it into thin slices against the grain.
4. In a medium mixing bowl, combine the butter, lemon, garlic, parsley, chives, mustard, salt, paprika, red pepper flakes and cayenne pepper. This works best to mash with a fork or the back of a spoon. You can also combine it using a paddle attachment on a stand mixer.
5. Place the butter in an airtight container or roll into a log on parchment or wax paper and refrigerate for 1 hour before using.
6. Melt the butter in a small saucepan or microwave.
7. Toast the bread on both sides under a low broil in the oven. Once the bread is toasted, baste both sides with the melted cowboy butter, reserving the leftover butter. Add two slices of provolone cheese to 4 of the slices and return to a warm (but not on) oven to melt the cheese.
8. Generously slather the non-cheese bread with the garlic aioli, topping with arugula, sun dried tomato, caramelized onions (if using) provolone and slices of the sirloin steak.
9. Serve the reserved melted cowboy butter on the side for dipping, if desired.
10. If you’ve tried this recipe, come back and let us know how it was in the comments or star ratings.