Step by step method

1. Grease a 20cm square cake tin or slice tray.
2. In a large saucepan heat the syrup and sugar together, bring to the boil then simmer on a low heat for 5 - 10 minutes. Cooking time will vary but test it by dropping a little syrup into cold water – it should become brittle when ready. Mind that it does not burn.
3. Remove pot from heat and add the bicarb. Quickly mix it because the mixture will foam up instantly.
4. Pour immediately into the cake tin and leave to set then break into bite size chunks.