Prepare the Roof: Start by melting the chopped chocolate together with the whey-free cream and brandy in a saucepan over low heat. Stir continuously until smooth, then set aside to cool.

Make the Cake Batter: In a bowl, beat the eggs and butter until creamy. Gradually add the sugar, yogurt, and mix until well combined. Sift in the wheat flour, chocolate powder, and baking powder, folding until just combined. Slowly add in the milk and cocoa liqueur, mixing until smooth.

Bake the Cake: Preheat your oven to 180°C (350°F) and pour the batter into a greased cake pan. Bake for about 30-35 minutes, or until a toothpick inserted into the center comes out clean. Allow cooling before layering.

Prepare the Mousse: In a blender, purée the fresh strawberries until smooth. Transfer to a saucepan, add sugar and cornstarch, cooking over medium heat until thickened. Let it cool.

Assemble the Cake: Once the cake is cool, layer the mousse on top and then pour the cooled chocolate roof over it. Allow it to set in the refrigerator for at least 2 hours before serving.