Honeycomb toffee, sponge toffee, cinder toffee or hokey pokey is a sugary toffee with a light, rigid, sponge-like texture. Its main ingredients are typically brown sugar, corn syrup (or molasses or golden syrup in the Commonwealth of Nations) and baking soda, sometimes with an acid such as vinegar. The baking soda and acid react to form carbon dioxide which is trapped in the highly viscous mixture. When acid is not used, thermal decomposition of the baking soda releases carbon dioxide. The sponge-like structure is formed while the sugar is liquid, then the toffee sets hard. The candy goes by a variety of names and regional variants.