Lightly brush the surfaces of the steaks with the marinade and set aside for 45 minutes, the steak should remain at room temperature while marinating.
Season the marinade steaks with the salt and firmly press the black pepper onto the surfaces of the steak
Prepare grill and cook steaks over direct high heat untildesired doneness, 8-10 minutes for medium rare. Turn the steaks once while cooking.
For the sauce:
Heat olive oil in a small sauté pot over low heat. Add garlic, shallots, and salt and cook 3-4 minutes, stirring often. Add cognac and brown sugar and cook 5-6 minutes, until thick and syrupy. Add demi glace* and cook until the mixture has reduced by half. Add the cream and cook until the sauce has reduced by half. Remove from the heat and stir in the mustard.
Top each cooked steak with 1-2 ounces of sauce.
Yield: 6 servings