Preheat the oven to 180 °C on a fan forced setting and lightly grease a 15-20cm cake tin.
Mix the almond milk and apple cider vinegar together and set aside to create a buttermilk.
Add buttermilk, pumpkin mash, maple syrup, milk, butter and vanilla to a blender or food processor and blitz until smooth.
Transfer into a large bowl and sift in the flour, coconut sugar, cinnamon, nutmeg and salt. Mix ingredients together until just combined, then fold in the grated carrot and nuts.
Pour mixture into cake tin and bake for 25 minutes, or until a skewer comes out clean.
Create the icing by whisking the cream cheese, coconut yoghurt and maple syrup together, until smooth.
Allow the cake to cool slightly before icing.