450g (1lb) Soft Brown Sugar
225g (8oz) Black Treacle
110g (4oz) Unsalted Butter
2 tbsp Water
1 tbsp White Vinegar
* Place the butter, water and vinegar into a heavy bottomed saucepan, heat gently until the butter has melted.
* Add the sugar and black treacle, allow to fully dissolve, this takes about 20 minutes.
* Boil the mixture to a temperature of 138°C (280°F).
* Remove from the heat, allow the bubble to decrease.
* Pour the mixture into a well oiled 18cm (7 inch) sandwich tin.
* When the mixture has cooled a little mark the surface into squares with a knife.
* When cold break into squares, wrap in cellophane and store in an airtight container.