Soak the cashews/macadamias (for the icing) and the dates (for the cake) in enough water to cover.
Line a cake pan or similar-sized container with parchment paper
Make the icing:
Drain the cashews/macadamias. Put all icing ingredients into a food processor and whizz until very smooth. Add water to thin the mixture. It should be the consistency of typical cake icing. Remove icing and chill in fridge.
Make the cake:
Drain the dates. Add the dates, oats and coconut to your food processor and process until the dates form a paste and the oats are almost fine crumbs.
Add the nuts and spices to the food processor. Process until it the nuts have broken down. Add the grated carrots, salt and vanilla (to taste) and process until the mixture has reached your desired consistency.
Press cake mixture into baking tin/container and spread icing over it.
Set aside in fridge or enjoy immediately. Slice before serving.