4 (10 to 12 ounces) sirloin steaks, trimmed
Salt
1 cup black peppercorns
1/2 cup plus 1 tablespoon Dijon mustard
2 tablespoons olive oil
1 pound baking white potatoes, peeled
Oil for frying
1/2 cup minced shallots
1 clove of garlic, peeled
1/4 cup brandy
1 cup demi-glace
1/4 cup heavy cream
1 tablespoon finely chopped fresh parsley leaves

Season the steaks with salt. In a coffee grinder, add the peppercorns and coarsely ground. With a small knife, spread a tablespoon of mustard on one side. Pack the peppercorns into the steak. Turn the steaks over and spread another tablespoon of mustard. Pack the peppercorns into the steak on the second side. In a large skillet, over medium heat, add the oil. When the oil is hot, add the steaks and sear for 4 to 5 minutes on each side. Remove the steaks from the pan. Using a mandolin, fitted with a waffle blade, cut the potatoes thinly, in a criss-cross motion, to form a waffle like chip. Fry until golden brown, about 4 to 5 minutes, stirring occasionally for overall browning. Remove and drain on paper towels. Season with salt. Set aside. Add the shallots and garlic to the pan. Sauté for 15 seconds. Carefully add the brandy and flame. Add the demi-glace, cream and mustard. Mix well. Bring the liquid to a simmer and cook for 1 minute. Add the steaks back into the pan and continue to cook for 1 minute on each side. Remove the steaks and place in the center of each plate. Stir the parsley into the sauce and spoon on top of each steak. Serve each steak with a pile of the potatoes