This is based on a recipe my grandma and my mum always used to make when we had a birthday to celebrate. It’s failsafe, super moist and lasts for days. The heavenly fudge frosting is silky smooth and stays that way once the cake is frosted, rather than setting over time. One tip I’ve learned for the lightest and smoothest end result, is to make sure your butter is really soft before making the frosting.