Line a 20cm square tin with clingfilm or parchment paper and set aside

Once cooled enough, put into the fridge to set

Once the tiffin base is set, melt the safe chocolate either over a bain marie or in short blasts in the microwave

Let cool slightly before pouring over the top of the tiffin base and let set back in the fridge

You can add any dried fruits, nuts or even pieces of chopped honeycomb or marshmallow to the base sauce

To turn this into a more Christmas flavoured Tiffin, swap the shortbread cookies for ginger ones, swap the cherries for dried cranberries and add in the grated zest of half an orange, 1/2 tsp ground cinnamon and 1/4 tsp ground cinnamon. You can also swap 100g of the topping chocolate for a safe white chocolate and marble the topping