1.Grease a tin.
2. Place all the ingredients in a large saucepan and heat until the butter has melted and sugar has dissolved.
3. Bring the mixture to the boil. It is important to stir continuously at this point so the mixture doesn't stick to the bottom of the pan.
4. Bring the mixture down to simmer for approximately 10 minutes. The mixture should be thick and the colour should have turned from white to caramel.
5. Take the pan from the hob and place it on a heat resistant surface for about 5 minutes.
6. After the 5 minutes beat the mixture really hard. At this point it will start to set.
7. Before the mixture sets, use a wooden spoon to transfer it into the prepared tin. You will find it sets almost straight away.
8. Before it has completely set, cut the tablet into bite size pieces and leave it to cool and set hard for 5 minutes.
||170ml/6 Floz/three Quarters Cup
||60g/2oz/one Quarter Cup