Chocolate cake

1. Preheat the oven to 170°C / 340°F and line two 20 cm / 8-inch cake pans with parchment paper.
2. In a large bowl, whisk together the cake flour, cocoa powder, baking powder, baking soda, and salt.
3. In another bowl, whisk the eggs, sugar, melted butter, vegetable oil, vanilla extract, and buttermilk until smooth.
4. Add the dry ingredients into the wet ingredients and mix just until combined.
5. Pour in the hot coffee and gently mix until smooth.
6. Divide the chocolate cake batter evenly between the prepared cake pans.
7. Bake for about 45 minutes or until a toothpick inserted in the center comes out with a few moist crumbs.
8. Let the chocolate cake layers cool completely before assembling.

Chocolate fudge frosting

1. Place the finely chopped dark chocolate in a large bowl.
2. Heat the heavy cream until hot and just simmering, then pour it over the chocolate.
3. Let sit for 1 minute, then stir until smooth and melted.
4. Add the softened butter, powdered sugar, vanilla extract, and salt and mix until creamy.
5. Let the chocolate fudge frosting cool at room temperature until thick and spreadable.

Assembly

1. Place the first chocolate cake layer on a serving plate and spread a thick layer of fudge frosting on top.
2. Add the second cake layer and finish with the remaining chocolate frosting using an offset spatula for a simple homemade finish.