Sponge Toffee

Line an 8×8-inch baking dish with foil and butter generously. Set aside.

Heat the sugar and syrup in a saucepan. (Make sure your saucepan is big enough for when you add the baking soda and it bubbles up.) Bring to a boil over medium-high heat. Cook until it reaches 285F.

Remove from the heat and stir in the baking soda. Stir well so that all of the baking soda will dissolve. Be careful – the mixture will bubble up and it is extremely hot.

Pour the mixture in the prepared pan to cool.

When cooled, break into pieces. Dip in tempered chocolate. Place on a piece of waxed paper to set.