Its super easy!
200g caster sugar and 4 tbsp of golden syrup in a pan and let it melt and then bubble until it turns dark like maple syrup (dont stir!). When that happens add 1TBSP of bicarbonate of soda and mix off the heat. It bubbles up and expands loads. Quickly pour into a tin lined with greaseproof paper, leave it to set and thats it !