Preheat the grill.
To French the lamb chops, strip the bone of flesh and fat above the eye of the chop. Season the lamb chops with olive oil and Essence. Place the chops on the grill and cook for 2 minutes on each side. Remove the lamb from the grill and cool. In a mixing bowl, mix the cheese, pine nuts, garlic, and chervil together. Mix well and season with salt and pepper. Using a sharp knife, make a 1 inch slit on one side of each chop. Stuff each chop with 1/4 cup of the filling. Rub the mustard over each chop evenly. Make a slit in the center of each piece of puff pastry. Slide the square of puff pastry down the bone of the chop. Bring the ends of the pastry together, and seal completely. Using your hands, form the pastry neatly so it resembles the original shape of the lamb chop. Place the lamb chops on a parchment lined baking sheet. Brush each chop with the egg wash. Place the chops in a preheated 400-425 degree oven for 10 to 12 minutes. Turn temperature down to 350 and continue to bake for about 8 to 10 minutes longer, or until the pastry is golden brown. Remove from the oven and serve two chops per person. Serve the chops with the hot demi-glace mixture and fresh rosemary sprigs.
Note: If you can't find Colorado Lamb chops, substitute New Zealand lamb chops. If you do substitute, increase the number of chops to three per person. Stuff each chop with 2 tablespoons of the filling instead of 1/4 cup. Also, increase the squares of puff pastry to 12 squares ( 3 inches by 3 inches).
Yield: 4 servings