Dissolve Cacao Powder (1 1/4 teaspoon), Granulated Erythritol (1 teaspoon), Ground Cinnamon (1 dash) and Vanilla Extract (1/4 teaspoon) into Water (80 gram). Let it cool down to lukewarm.
Then bring pot to low heat and stirring constantly with a whisk, pour in the Egg (3). Keep stirring until mixture reach simmering point and thickens up.
Remove from the heat and stir for 1 more minute. Pour into serving cups and refrigerate for 4 hours or overnight.
Serve with a handful of berries or crushed nuts or just plain.