Preheat the oven to 175°C / 350°F. Proper preheating ensures even baking from the moment the cakes go into the oven.
Line two 8-inch (20 cm) round cake pans with parchment paper and grease them well. This step prevents sticking and allows for easy removal after baking.
In a large mixing bowl, whisk together the flour, cocoa powder, sugar, baking powder, baking soda, and salt until evenly combined. This ensures that the leavening agents and cocoa are distributed uniformly throughout the batter.
Add the eggs, vegetable oil, buttermilk, and vanilla extract to the dry ingredients. Mix until the batter is smooth and free of dry pockets. The texture should be thick and glossy at this stage.
Slowly pour in the hot water while mixing gently. The batter will become thin and fluid, which is expected and helps create a moist, tender cake crumb.
Divide the batter evenly between the prepared pans, tapping them lightly on the counter to release any air bubbles.
Bake for 28–32 minutes, or until a toothpick inserted into the center comes out clean with only a few moist crumbs attached.
Remove the cakes from the oven and allow them to cool completely in their pans before assembling. Cooling fully is essential to prevent the cream from melting during assembly.
Prepare the Chocolate Cream
In a large chilled bowl, whip the heavy cream and powdered sugar together until soft peaks form. The cream should hold its shape gently without becoming stiff or grainy.
Pour in the melted and cooled dark chocolate along with the vanilla extract. The chocolate must be cooled to avoid deflating the cream.
Beat again until the mixture becomes thick, fluffy, and fully combined. The finished cream should be smooth, stable, and spreadable.
Sweeten the Strawberries
Toss the sliced strawberries with sugar, if using, in a small bowl.
Let them rest for about 5 minutes. This draws out their natural juices and creates a lightly syrupy texture that layers beautifully in the cake.
