Preheat the oven at 365F or 185C. Cove the base of a round cake mold (20 cm diameter by 8 cm height) with waxed paper.
Sieve the flour with powdered cocoa twice, to combine completely.
In a bowl combine the eggs, sugar, salt, and vanilla using a hand mixer. Place on Bain Marie and allow to heat to 115F or 46C. Remove from Bain Marie — careful, the bowl will be hot– and beat with electric mixer on high until the mix rises and is very frothy, about 6 minutes or more.
Sprinkle 1/3 of the flour add cocoa mix and using a spatula and combine everything gently,  repeat with the next 1/3 and finally add the last 1/3. Add the melted butter and incorporate into the mix, always taking care of not collapsing the mix. Just stir very gently.
Place in the mold and bake for 35-40 minutes until a toothpick inserted in the center comes out clean.
Let cool on the mold. Refrigerate in the same mold if you are preparing it the next day.

Note: I used 2 molds, but it wasn’t a good idea,  it did not rise well. So use one mold.

For the syrup, place the water and sugar in a small pot, heat until sugar dissolves, allow to cool. Add liquor, stir.

Beat cream at high speed (I always refrigerate the bowl and beaters for about 5 minutes) until soft waves form, add sugar slowly, beat again at high speed until firm or Chantilly.
Unmold the cake, loosen with a knife and turn over on a plate. Make a dent on the cake before layering as a reference when mounting the cake.
Divide the cake into 3 layers using a long serrated knife, and saw and keep rotating the cake at the same time.
Separate the layers.

Place the first layer on a plate and sprinkle 1/3 of the syrup. Add 1/3 of the jam and one layer of 1 cm of cream. Repeat. Cover with a thin layer of cream and refrigerate for 1 hour. Keep the rest of the cream refrigerated.

Decorate to your taste. Keep refrigerated.