For Crust • cups buttercookies, crushed, I used Pepperidge Chessman butter cookies • melted butter • For Hazelnut Chocolate Mousse • hazelnut milk chocolate bars, crushed, I used Lindt classic recipe milk chocolate with roasted hazelnut bars • heavy whipping cream • vanilla extract • For Garnish • shaved hazelnut chocole bar,as needed • whipped cream as needed for serving