1. Preheat the oven to 350°F and line the bottom of a 9-inch springform pan with parchment paper. Lightly grease the sides.

2. In a mixing bowl, whisk together flour, cocoa powder, sugar, baking powder, baking soda, and salt.

3. Add egg, milk, oil, and vanilla extract. Mix until smooth, then stir in hot coffee or hot water until the batter is thin and glossy.

4. Pour the batter into the prepared pan and bake for 18 to 22 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.

5. Let the cake cool completely in the pan before adding the mousse layers.

6. Stir raspberry preserves with lemon juice, then spread the mixture over the cooled cake base. Scatter fresh raspberries over the preserves.

7. Sprinkle gelatin over cold water and let it bloom for 5 minutes. Warm gently until dissolved, then let it cool slightly.

8. Beat softened cream cheese with powdered sugar and vanilla until smooth.

9. Mix the melted and cooled chocolate into the cream cheese mixture until fully combined.

10. Add the dissolved gelatin and mix until smooth.

11. In a separate bowl, whip heavy cream to soft peaks, then gently fold it into the chocolate mixture until light and even.

12. Spread the chocolate mousse over the raspberry layer and smooth the top.

13. Refrigerate the cake for at least 6 hours, or overnight, until fully set.

14. For the ganache, heat heavy cream until steaming, then pour it over chopped chocolate. Let it sit for 1 minute, then stir until glossy.

15. Pour the slightly cooled ganache over the chilled mousse cake and spread gently.

16. Chill for 20 to 30 minutes, then garnish with fresh raspberries and chocolate curls before slicing.