Mix the marinade ingredients in a large pan. Lay the leg of lamb in and turn to coat on all sides. Cover with plastic wrap and refrigerate.

Let the lamb marinate for 12-24 hours, turning in the marinade a few times.

Remove the lamb from the refrigerator and allow it to come to room temperature.

Meanwhile, combine the oregano, rosemary, thyme, parsley, Kosher salt, minced garlic, olive oil, and Dijon mustard in a small bowl stirring to create a paste.

Lightly dry off the leg of lamb with a paper towel and generously rub with the paste on all sides.

Prepare the grill to cook the lamb using the indirect method. You should have one side of your grill very hot and the other side cool.

Start by cooking the lamb over direct heat until charred on all sides.

Move the lamb to the cooler side of the grill and continue to cook on indirect heat with the lid closed for 1 1/4 to 1 3/4 hours or until the lamb registers about 135 - 140 degrees F.

Allow the lamb to rest for 15 min. before slicing.