Prepare 2 molds and cover them with paper.

Combine dry ingredients (flour, baking powder, cocoa, salt) and sift together.

Preheat oven to 170C (338F).

Cream unsalted butter in a bowl until smooth.

Gradually add granulated sugar and salt to the butter, mixing until light and fluffy.

Incorporate whisked eggs and vanilla extract into the butter mixture, mixing well.

Gently fold in the sifted dry ingredients until just combined, creating a glaze-like batter.

Divide the batter in half.

Add cocoa to one half of the batter and mix until evenly colored.

Pour each batter (chocolate and vanilla) into separate prepared molds, creating an indent in the center of each.

Bake in the preheated oven for 35-40 minutes, or until a toothpick inserted into the center comes out clean.

Remove the cakes from the molds and let them cool completely on a wire rack.

For the Chocolate Glacage: Soak gelatin in three times its weight in cold water.

Combine water, granulated sugar, and cocoa in a saucepan.

Heat the mixture until the sugar and cocoa are dissolved and smooth.

Add heavy cream and bring the mixture to a boil, then remove from heat.

Stir in the bloomed gelatin until completely dissolved.

Strain the glacage once to remove any lumps and let it cool to skin temperature.

To Assemble: Level the tops of the cooled cakes and slice each into two 2cm thick layers, yielding a total of 4 layers.

Cut large (8cm diameter) rounds from the cakes, alternating the cocoa and vanilla layers when stacking.

Cut smaller (4cm diameter) circles from the center of each layer, swapping the cutouts between the cocoa and vanilla layers.

Thinly coat each layer with the prepared frosting, and stack the layers alternating the cocoa and vanilla flavors.

Coat all sides of the assembled cake with the remaining frosting to create a glacage.

Chill the cake until the glacage is set and firm.

Create chocolate decorations as desired.

Decorate the chilled cake with the chocolate decorations and serve.

Heat chocolate syrup in a hot water bath.

Add gelatin that has been dissolved in water.