Tart: Bring the butter and eggs to room temperature. Sieve the flour and cocoa together. Spread the butter in the mold and let it cool.
Add powdered sugar to the butter in 3 batches and whip together with a whisk. Add the beaten egg slowly.
Add the sieved flours to mix with a spatula. When the mixture becomes together, wrap it up with a plastic wrap, rest for more than 30 minutes in fridge.
Roll up the dough larger than a tart pan to line on. Push with your fingers. Cut off the excess dough, pierce with a fork. Keep it until when you need it.
Chocolate cream: Bring the egg to room temperature. Sieve the almond flour, chop the chocolate, put it into a pot with heavy cream. Melt them in double broiler.
Add the granulated sugar into the egg, mix well with a whisk. Add the dissolved chocolate slowly.
Add the almond flour, mix until smooth texture. Wrap the bowl to rest for 15 minutes in fridge.
Crush the chocolate flakes lightly, and line on the bottom of tart pan.
Pour the chocolate cream, tap the pan lightly on the counter to remove air bubbles. Bake for 20 - 25 minutes at 170°C. When it has cooled, take it out from the pan.
Syrup: Turn on the heat an stir the water and granulated sugar to melt. Add the rum.
Cheese cream: Bring the cream cheese to room temperature. Soak the gelatin sheets in water. Whip the heavy cream until it forms soft peaks.
Add the granulated sugar into cream cheese to mix. Dissolve the soaked gelatin in double broiler and mix into cream cheese. Add the rum, too.
Add the heavy cream little by little to mix together, then add them all. Put the cream in icing bags with a tip.
Finishing: Pour the syrup on the chocolate cream (not to put on the tart), then squeeze out the cheese cream. Sprinkle the chopped pistachios.
The cut out parts look like this.