In a large bowl, combine the almond flour, cocoa powder, and granular erythritol.

Stir in the melted butter until the mixture resembles wet sand.

Press this mixture evenly into the bottom of a 22 cm (approximately 9-inch) springform pan, ensuring it goes up the sides about 3-4 cm.

Place the crust in the refrigerator to cool while you make the filling.

In a saucepan, combine the water and gelatin, letting it sit for 1 minute to bloom.

Add 400 ml of heavy cream and heat the mixture over medium heat, whisking continuously until the gelatin is fully dissolved and the mixture is warm.

In a medium bowl, whisk together the egg yolks and powdered erythritol until smooth.

Gradually add 250 ml of the warm cream mixture to the yolks, whisking to combine.

Pour the yolk mixture back into the saucepan with the remaining cream and cook over low heat, stirring constantly, until it thickens to a pudding-like consistency.

Remove the saucepan from the heat and stir in the green food coloring and mint extract.

Allow the mixture to cool to room temperature.

In a separate bowl, whip the remaining 200 ml of heavy cream to stiff peaks.

Gently fold the whipped cream into the cooled mint mixture until well combined.

Pour the mint filling over the chilled crust, smoothing the top with a spatula.

Sprinkle chopped dark chocolate over the top for garnish.

Refrigerate the cake for at least 3 hours to allow it to set fully.