The Frankfurter Kranz (or Frankfurt Crown Cake) is a cake speciality from Frankfurt am Main. Shaped like a crown in a ring shape, it is filled with buttercream (and also possibly jam or jelly) and topped with caramel-covered brittle nuts, called Krokant. Butter cream or buttercream or mock cream is a type of icing used inside cakes as a coating and as decoration. Brittles are Confections usually very hard and brittle made of Caramel, or near-caramel sugar syrup and nuts such as peanuts pecans and almonds