Caramel shortbread, also known as caramel shortcake, caramel squares, caramel slice, millionaires' shortbread, and millionaires' slice, is a biscuit confectionery item composed of a rectangular shortbread biscuit base topped with a very soft caramel filling and a milk chocolate topping. Some of the first known recipes and references are in Australian journals and cookbooks from the 1970s, most notably in The Australian Women's Weekly.