Make the Chocolate Cake Base:

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease and line a 9-inch springform pan with parchment paper.
2. Mix Dry Ingredients: In a medium bowl, whisk together flour, cocoa powder, baking powder, baking soda, and salt.
3. Cream Butter and Sugar: In a large bowl, beat butter and sugar with an electric mixer until light and fluffy.
4. Add Eggs: Beat in eggs one at a time, followed by the vanilla extract.
5. Combine Wet and Dry: Alternate adding the dry ingredients and milk to the batter, beginning and ending with the dry ingredients. Stir in the hot coffee or water until smooth.
6. Bake: Pour the batter into the prepared pan and bake for 25-30 minutes or until a toothpick inserted in the center comes out clean. Let the cake cool completely.

Prepare the Raspberry Mousse:

7. Make Raspberry Puree: Blend fresh raspberries into a smooth puree and strain through a sieve to remove seeds.
8. Cook with Sugar: In a small saucepan, heat the raspberry puree with sugar over medium heat until the sugar dissolves.
9. Add Gelatin: Dissolve gelatin in water and mix it into the warm raspberry mixture. Allow it to cool to room temperature.
10. Fold in Whipped Cream: Gently fold the cooled raspberry mixture into the whipped cream.

Prepare the Chocolate Mousse:

11. Whip Cream: In a large bowl, whip the heavy cream with powdered sugar until soft peaks form.
12. Combine with Chocolate: Fold the whipped cream into the cooled melted chocolate until smooth and creamy.

Assemble the Cake:

13. Layer the Cake Base: Place the cooled cake layer in the bottom of a 9-inch springform pan.
14. Add Raspberry Mousse: Spread the raspberry mousse evenly over the cake layer and chill for 1 hour to set.
15. Add Chocolate Mousse: Spread the chocolate mousse over the set raspberry mousse and chill for another hour.

Prepare the Ganache:

16. Heat Cream: In a small saucepan, heat the cream until just simmering.
17. Combine with Chocolate: Pour the hot cream over chopped chocolate and let it sit for 2 minutes. Stir until smooth.
18. Spread Ganache: Pour the ganache over the top of the cake and smooth with a spatula. Chill for 1 hour to set.

Serve:

19. Garnish and Slice: Decorate with fresh raspberries and chocolate shavings. Slice and serve chilled.