1. Prepare the pan.
Preheat the oven to 350°F (175°C). Lightly grease a 9-inch springform pan and line the bottom with parchment paper.

2. Combine the dry ingredients.
In a medium bowl, whisk together the flour, cocoa powder, baking powder, and salt until evenly combined.

3. Mix the wet ingredients.
In a large bowl, whisk the eggs, granulated sugar, and brown sugar for about 1 minute. Add the milk, vegetable oil, and vanilla and whisk until smooth.

4. Finish the batter.
Add the dry ingredients to the wet mixture and fold gently just until no dry flour remains. Do not overmix.

5. Bake.
Pour the batter into the prepared pan and level the surface. Bake for 20–25 minutes, until a toothpick inserted into the center comes out with a few moist crumbs but no wet batter.

6. Cool completely.
Place the pan on a wire rack and allow the chocolate cake to cool completely without removing it from the springform pan. If the cake has a pronounced dome, carefully level it once completely cool.

7. Cook the raspberries.
Place raspberries, sugar, and lemon juice in a saucepan. Cook over medium heat for 4–5 minutes, stirring gently. Allow some berries to break down while leaving plenty of visible pieces.

8. Thicken the topping.
Mix the cornstarch with 3 tablespoons cold water until completely smooth. Stir it into the raspberry mixture and cook for another 1–2 minutes, stirring frequently, until thick and glossy. Transfer to a bowl and cool completely.

9. Prepare the cream.
Beat softened cream cheese, powdered sugar, and vanilla until completely smooth.

10. Whip the cream.
In a separate clean bowl, whip the cold heavy cream until stiff peaks form. Do not overwhip.

11. Combine.
Gently fold the whipped cream into the cream cheese mixture in three additions until fluffy, thick, and uniform.

12. Build the cream layer.
Leave the cooled chocolate cake inside the springform ring. Spread the vanilla cream evenly over the cake, taking it all the way to the edges and smoothing the surface.

13. First chill.
Refrigerate for 30–45 minutes so the cream begins to firm.

14. Add the raspberry layer.
Make absolutely sure the raspberry mixture is completely cold. Spoon it gently over the chilled cream and spread without pressing down heavily. Keep some visible berry texture rather than making the surface perfectly smooth.

15. Final chill.
Cover without touching the topping and refrigerate for at least 6 hours, preferably overnight.

16. Unmold and serve.
Carefully run a thin knife around the edge if necessary, release the springform ring, and slice with a clean sharp knife. For clean layers, warm the knife in hot water, dry it thoroughly, and wipe it clean between every cut.