Chocolate cake

1. Preheat the oven to 329°F (165°C) and line three 6-inch (15 cm) round cake pans with parchment paper.
2. In a bowl, sift together the cake flour, cocoa powder, baking soda, baking powder, and salt.
3. In a large bowl, beat the eggs, sugar, vanilla, and oil for about 2 minutes until pale and smooth.
4. Add the buttermilk and hot coffee (or water) and mix again.
5. Add the dry ingredients in batches and gently whisk until smooth and lump-free.
6. Divide the batter evenly between the pans.
7. Bake for about 35-40 minutes if baking all pans at once, or about 20 minutes per batch if using one pan.
8. Check doneness with a toothpick; it should come out clean or with a few crumbs.
9. Let cool slightly, then unmold and cool completely upside down on a rack.
10. Wrap and refrigerate for at least 2 hours before assembly.

Whipped chocolate ganache

1. Finely chop the chocolate and place it in a bowl.
2. Heat 400 ml of heavy cream to a simmer and pour it gradually over the chocolate, stirring to form a smooth emulsion.
3. Add the cold heavy cream and mix until fully incorporated.
4. Blend briefly with an immersion blender if needed.
5. Cover and refrigerate overnight (minimum 6 hours).

Assembly and decoration

1. Level the cake layers.
2. Whip the cold ganache for about 3 minutes until smooth and firm.
3. Transfer the ganache to a piping bag.
4. Place the first cake layer on a cake board and turntable, spread ganache, add strawberries, and cover with more ganache.
5. Repeat with the remaining layers.
6. Apply a thin crumb coat, chill for 20 minutes, then frost the cake completely.
7. Decorate with ganache and strawberries.
8. Refrigerate the finished cake for at least 2 hours before serving.