Crumb Cake is a delicious treat that can be enjoyed for breakfast or dessert. It consists of a soft and moist cake with a thick layer of crumbly streusel topping, baked to perfection, and dusted with confectioners' sugar. The cake is so good that there won't be any crumbs left behind on anyone's plate. It is made with ingredients like butter, sugar, cake flour, buttermilk, eggs, and confectioners' sugar. The cake should be stored at room temperature and can be frozen for longer storage. This recipe is adapted from America's Test Kitchen.