1. For the cocoa sponge-cake separate the egg yolks and beat the egg whites until stiff.

2. Add the dry ingredients to the yolks, add the coconut flour, a little at a time, and stir it continuously. Finally add the beaten egg whites.

3. Pour the batter into a silicone cake pan and fan-bake it for 12-15 minutes at 180°C (350°F). Use a cake testing needle to see if it’s done.

4. Wait until the sponge-cake cools completely and crumble it into a bowl.

5. Add the butter, the cheese cream and the ground almonds and combine them with your hands.

6. Squeeze the mixture into silicon muffin cups and rest it in the fridge for half an hour.

7. While it is resting you can prepare the sugar-free icing. Add as much powdered sweetener to one egg white as you need for a mixture thick enough to cover your tarts. Add a few drops of vinegar (this will make it shiny) and a teaspoon of konjac flour or starch and stir until combined.

8. Divide the mixture into as many part as many colours you want to use and food-dye each one with a different color. Be careful with the dye, a few drops are enough.

9. Get the tarts from the fridge and remove them from the silicone cups and put them into paper cups instead because the icing may drip at the sides.

10. Use a spoon to apply the icing on the tarts.

11. You can also decorate your tarts with sugar-free marzipan figures. See the recipe here.