Rocky road, tiffin and fridge cake are all so similar that they could almost be considered the same thing. All are a form of no-bake chocolate slice with add-ins stirred through and then chilled. However, tiffin is generally made with cocoa powder and is more comparable to a hedgehog slice. Chopped biscuits are one of the main add-ins used in tiffin and fridge cake, whereas rocky road is famous for it's marshmallow filling.