Yes, it's a breeze to make this carrot cake in advance. My preference is to bake the traybake the night before and leave it to cool overnight, covered with a tea towel. Then, in the morning, I whip up the icing, spread it over the cake, sprinkle with walnuts and serve. Alternatively, you can make the whole carrot cake tray bake the night before, cream cheese icing and all, then pop it in a sealed container in the fridge to enjoy the next day.