Preheat your oven to 180 °C (around 350 °F).
Line a small (12 cm) round cake tin for baking. Use a small piece of baking paper, dipped in softened butter and smear it around the inside of the tin.
In a large bowl mix the butter and artificial sweetener together.
Add the remaining liquid ingredients; the vanilla essence, soy milk and eggs.
Beat with a mixer until well-combined and there are no lumps of butter remaining.
Next add the dry ingredients; almond flour, coconut flour, baking powder, cinnamon and all spice. Mix until a smooth batter is formed.
Transfer half of the mixture to the prepared cake tin and bake for around 20-22 minutes. To test when ready, insert a toothpick in the center of the cake. When it comes out clean your cake is done!
Allow the cake to completely cool, before removing from the baking tin. Wash your cake tin and repeat the baking process with the remaining half of the cake batter.