I recommend soaking all the dates beforehand in the plant-based milk that you will use for frosting for 1 hour to overnight this will ensure a smooth blending and will make the milk sweeter.
Briefly roast your hazelnuts on the frying pan for a few minutes till they pick up some color. After cool enough to handle peel most of the skins off just by rubbing them with your hands or between two clean tea towels.
Combine 1 tbsp flax meal with 3 tbsp of water or plant-based milk to form an egg and set aside for 15 minutes
Preheat the oven to 180 degrees
Blend hazelnuts with rice flour till the fine flour consistency, stir in baking soda
Blend dates with coconut oil, apple cider vinegar and flax egg until completely smooth.
Stir dry ingredients in.
With an electric whisk whip aquafaba till soft picks consistency and carefully fold in the batter, transfer straight away to your cake tin and bake for 35-45 minutes till bouncing back when you touch it and tooth pick inserted in the centre comes out clean.Leave to cool completely
When ready to frost blending all the ingredients for the chocolate cream until completely smooth.
Slice the cake in half and spread 1/3 of the cream, top with roasted hazelnuts and place the other layer on top and finish the frosting with the rest of the cream.