Boil the chestnuts, remove the shells, and mash them finely.
Whip the cream cheese and erythritol until smooth.
Whip the heavy cream until stiff peaks form.
Mix the mashed chestnuts, whipped cream, and cream cheese to make chestnut cream.
Make a keto cake sheet with almond flour, eggs, erythritol, baking powder, and vanilla extract.
Bake the keto sheet in the oven and let it cool.
Mix espresso and stevia to make a syrup.
Soak the baked sheet with espresso syrup.
Layer the soaked sheet with chestnut cream and repeat several layers.
Dust cocoa powder on the top layer to finish.