While pre-heating oven to 180 °C combine together (in a small bowl) coconut flour, cocoa and baking powder. Make sure there are no visible chunks as they will re-surface once the muffins are baked (which does not look nice).
In a big bowl mix together eggs, heavy cream and sweetener.
Melt butter and chocolate and add to wet ingredients.
Add dry ingredient mixture to wet ingredients and mix for several minutes (until you get one consistent batter).
Fill cupcake molds evenly. I prefer small ones (~ 15 to 17 with this mixture).
Bake for ~20 minutes or until stable/hard enough (you can softly press the muffin to with your finger and check for sufficient integrity).