- 75g unsalted butter
- 200g golden syrup
- 400g caster sugar
- 1 tsp malt vinegar (or wine vinegar)
- 2 level tbsp bicarbonate of soda
- Melted chocolate, for dipping
Line a shallow 22cm square cake tin with baking paper
Put the butter, syrup, sugar and 4 tbsp water in a large pan and stir gently, over a medium heat, until the sugar dissolves. Try not to splash the mixture up the sides of the pan as you stir. Increase the heat to high and bring the mixture to the boil.
Boil, without stirring, until a teaspoon of the mixture forms a hard ball when dropped into a bowl of cold water. If you have a sugar thermometer, the toffee is ready when it reaches 138C.
Immediately remove from the heat and add the vinegar and bicarbonate of soda. Be careful as the mixture will boil up and rise in the pan.
Stir once gently to mix everything together.
Pour immediately into the tin and leave until completely cold and set.
Break the set toffee into pieces with a rolling pin. Serve with melted chocolate for dipping.