Step 1

Line a 20 x 20cm square tin with baking paper. Make sure you leave paper hanging over the edge to help you remove the slice once it has set. Crush the biscuits into small pieces and place in a bowl until needed.

Step 2

Put the butter and golden syrup into a large saucepan and cook over a medium heat for 3 minutes, stirring regularly until melted and combined.

Step 3

Remove the saucepan from the heat and add the cocoa and raisins and stir to combine.

Step 4

Add the crushed biscuits and stir to combine before pouring the mixture into the prepared slice tin and pushing down with the back of a spoon to smooth the surface. Place the slice into the fridge.

Step 5

In the meantime, break the milk chocolate into pieces and place it into a microwave-safe bowl. Cook for 30 seconds on a high heat before giving it a good stir and cook for a further 30 seconds or until the chocolate has just melted. Pour the melted milk chocolate over the slice and place it back into the fridge for 2 hours to set. Cut the set slice into pieces and store in a covered container in the fridge for up to a week.