Chocolate Caramel Biscuit Recipe

Chocolate Caramel Biscuit Recipe - 50g of dark chocolate, 100ml of whole milk, 115g of dark muscovado sugar, 40g of unsalted butter, soft, 1 large egg, beaten, 1 tsp vanilla essence, 110g of plain flour, 1 tbsp of cocoa powder, 1 tsp bicarbonate of soda, 1 pinch of salt, 200g of light muscovado sugar, 80g of butter.