For the base: add the almonds and buckwheat grouts to a food processor and break down until the form a course crumb. Add the dates and cacao powder and blitx again until the mixture sticks together.
Press down evenly on to the base of a lined square baking tin, Set aside.
For the custard, melt down the cacao butter on low heat until liquid, place in blender along with all other filling ingredients and blend until smooth.
Pour over base and place in the fridge to set (not freezer) for about 4 hours or overnight.
Add chocolate shavings and slice into squares. Stores in the fridge but should be eaten within 3 days as the tofu gives off water.
Recipe by Talida Voinea at https://talidavoinea.au/vegan-chocolate-vanilla-custard-slice/