Cinder Toffee

Uploaded: 2 October, 2023



Part science experiment and part sweet treat. This is fun for the kids and perfect for Halloween and bonfire night.

Preparation time: 5 minutes

Cooking time: 15-20 minutes (plus cooling)

Ingredients - Serves: Depends on how sweet your tooth is!

165g demerara sugar

165g caster sugar

60ml golden syrup

4 tbsp water

15g butter, diced, plus extra to grease

Pinch of salt

1 tbsp bicarbonate of soda

*You will also need a kitchen thermometer


  • Generously grease an approximately 24cm square tin.
  • Put the bicarbonate of soda within easy reach of the hob.
  • Place both sugars, syrup, water, and butter in a deep, heavy-bottomed pan with a pinch of salt. (Make sure it is a deep pan or the ‘science bit’ will go horribly wrong!).
  • Heat gently, stirring, until the sugars and butter have dissolved, then turn up the heat slightly and bring to the boil. Simmer until it reaches 138C, turns amber and bubbles – this will take about 10-15 minutes.
  • When the mixture gets to temperature, remove it from the heat and quickly and thoroughly whisk in the bicarb. It will foam and grow alarmingly. The kids will love it!
  • Pour the foamy mixture into the tin and leave to set. When cold get the kids to smash it into pieces.
  • Optional: Pour melted chocolate over the shards for the ultimate cinder toffee treat.