1. Preheat oven to 170°C (338°F). Line a 40×42 cm (16–17 inch) tray with baking paper.

2. Sift flour, cocoa, salt, and vanilla powder together.

3. In another bowl, beat butter and sugar until fluffy.

4. Add eggs one at a time, mixing well after each.

5. Combine 2 tbsp batter with red food coloring and 1 tbsp buttermilk; set aside.

6. Add dry ingredients to the wet mixture in three batches, alternating with buttermilk. Mix gently.

7. Spread batter evenly in tray and bake for 20 minutes or until a toothpick comes out clean.

8. Cool completely on a wire rack.

9. Beat butter and powdered sugar until smooth for the cream base.

10. In another bowl, mix cream cheese and mascarpone until creamy.

11. Combine both mixtures and transfer to a piping bag with a 6 mm round tip.

12. Cut out 16 circles (7 cm diameter) from cooled cake.

13. Pipe cream on 8 circles, top with remaining 8, and add cream on top.

14. Refrigerate for several hours to chill.

15. Bring to room temperature for 15 minutes before serving.

16. Garnish with fresh berries and mint leaves.