In a bowl, combine softened butter, Dijon mustard, chives, parsley, thyme, garlic, lemon juice, paprika, salt, black pepper, cayenne, and red pepper flakes. Stir until smooth and creamy.

Let the boneless prime rib roast sit at room temperature for about 2 hours.

Set your oven temperature to 500°F.

Place the prime rib on a roasting rack and generously rub the mixture of cowboy butter all over the meat. Roast in the oven for 15 minutes.

After the initial sear, reduce the oven temperature to 325°F. Continue roasting for about 13-15 minutes per pound.

Once done, let the roast rest for 30 minutes before slicing against the grain.