Honeycomb & Cinder Toffee

Honeycomb toffee, also called cinder toffee, sponge toffee, or hokey pokey, is an aerated candy made by stirring baking soda into hot caramelized sugar syrup, which releases carbon dioxide and creates its airy, bubbly structure. It is cooked to the hard-crack stage so it sets crisp and light, and it is often coated in chocolate.

The Science of the Bubbles

When baking soda is added to hot sugar syrup, it decomposes and releases carbon dioxide gas, which foams up the molten toffee. As the candy cools and hardens quickly, those bubbles are trapped, giving honeycomb its signature porous, crunchy texture.

Names and Variations

The same candy goes by many names, including cinder toffee, sponge toffee, sea foam, and hokey pokey in New Zealand. It is commonly enrobed in chocolate, and success depends on reaching the right temperature and working quickly before the foam collapses.

Answers in Honeycomb & Cinder Toffee (24)

Frequently asked

What makes honeycomb toffee bubbly?
Baking soda stirred into hot sugar syrup releases carbon dioxide, and the bubbles are trapped as the toffee quickly cools and hardens.

Sources

By Kelsy Maruyama, Founder & Toffee Maker, Kelsy's Kandy

Reviewed by Jason Burns, Editorial Steward

Updated 7/20/2026.