4. Add the Hot Water (or Coffee):

Gradually add the hot water (or hot coffee) to the batter. The batter will be very thin, which is normal. This step helps keep the cake ultra-moist.

5. Bake the Cake:

Pour the batter evenly into the prepared cake pans.
Bake in the preheated oven for 30-35 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.
Let the cakes cool in the pans for about 10 minutes before transferring them to a wire rack to cool completely.
6. Prepare the Chocolate Ganache:

While the cakes are cooling, prepare the ganache. Place the chopped chocolate in a heatproof bowl.
In a small saucepan, heat the heavy cream over medium heat until it just begins to simmer (do not let it boil). Pour the hot cream over the chopped chocolate and let it sit for 2-3 minutes.
Stir the mixture gently until smooth and glossy. Add the butter (if using) for extra richness and stir until fully melted.
Let the ganache cool slightly before using it on the cake.
7. Assemble the Cake:

Once the cakes have cooled completely, place one layer of the cake on a serving platter.
Spread a generous amount of chocolate ganache on top of the first layer.
Place the second cake layer on top and frost the top and sides of the entire cake with the remaining ganache.