Chocolate Ganache (Prepared the Day Before)

1. Cut or chop the chocolate finely and place it in a heat-resistant bowl.
2. Heat half of the heavy cream in a saucepan until simmering, then pour it over the chocolate. Let it sit for a moment before gently mixing until you have a completely melted ganache.
3. Add the cold portion of heavy cream and mix to incorporate, then use an immersion blender to smooth out any lumps.
4. Cover with plastic wrap directly on the surface and let it rest in the refrigerator for at least 4-6 hours (ideally overnight).

Chocolate Molly Cake

1. Preheat the oven to 165°C (325°F) and line the bottom of three 15 cm (6 inch) cake pans with parchment paper.
2. In the bowl of your stand mixer fitted with the paddle attachment, whisk the eggs and sugar for 5 to 7 minutes until they are voluminous (the mixture should double or triple in volume).
3. Meanwhile, whip the cold heavy cream with an electric mixer until stiff peaks form.
4. Reduce the mixer speed and gently fold in the sifted dry ingredients: cake flour, unsweetened cocoa powder, baking powder, baking soda, and salt.
5. Using a hand spatula, gently fold in the whipped cream until the batter is homogeneous.
6. Divide the batter into 3 portions and distribute evenly into the prepared pans.
7. Bake in the oven for 40 to 45 minutes. (Check for doneness by inserting a toothpick into the center; it should come out clean.)
8. Carefully remove from the pans by running a knife around the edges, then allow the cakes to cool completely on a wire rack with the tops down to flatten the domes.

Chocolate Cremeux Filling

1. Line the bottom of two 12 cm (5 inch) round pans with a circle of parchment paper (or use pastry rings instead of pans).
2. Cut the chocolate into pieces and place it in a bowl.
3. In a saucepan, bring the milk and cream to a boil. Meanwhile, place the egg yolks and sugar in a bowl and whisk together.
4. Pour the hot milk and cream mixture over the yolks while continuing to whisk, then return everything to the saucepan, stirring constantly, and cook until it reaches a temperature of 83°C (181°F).
5. Pour this mixture over the chocolate, mix until smooth and creamy.
6. Divide this mixture between the two prepared pans and place in the freezer for at least 4 hours.

Assembly

1. Whip the ganache with an electric mixer on low speed for about 1 minute until it becomes firm and smooth. Transfer the ganache to a large piping bag.
2. Place the first cake layer on a revolving cake stand, apply a border of ganache, and place the frozen cremeux insert in the center.
3. Cover with a bit more ganache, then add another cake layer, repeating for the final cake layer.
4. Apply a thin layer of ganache over the entire cake and place the cake in the freezer for 10-15 minutes if possible to firm up the ganache.
5. Then apply a thicker layer of ganache all over the cake and smooth it with a metal icing smoother.
6. Return the cake to the refrigerator or freezer to firm up the covering ganache once again.

Decoration

1. Melt the dark chocolate with the heavy cream in a double boiler or microwave until you have a smooth, melted ganache. Let it sit for a few minutes (ideally 30-35°C or 86-95°F).
2. Pour the liquid ganache over the top of the chilled cake and let it drip over the edges using an offset spatula.
3. Decorate with chocolate shavings or sprinkles and return to the refrigerator for 1 hour before serving.