Start by preheating your oven to 350°F (175°C). This sets the foundation for even baking. While it warms up, grab your cake pans—two 9-inch round ones will do. Grease them well and dust them with flour to ensure your cake doesn’t stick.

In a medium bowl, whisk together the flour, cocoa powder, baking soda, and salt. This step is crucial as it ensures the baking soda is evenly distributed throughout your dry ingredients.

In a large mixing bowl, use an electric mixer to cream the softened unsalted butter and granulated sugar until light and fluffy, about 2-3 minutes. This process incorporates air, which is essential for a light cake.

Next, beat in the eggs one at a time, allowing each to incorporate fully. Add the vanilla extract and mix until combined.

Now it’s time to bring your dry and wet ingredients together. Alternate between adding the flour mixture and buttermilk to the butter mixture, starting and ending with the dry ingredients. Mix on low speed just until combined—overmixing can lead to a dense cake.

Divide the batter evenly between the prepared cake pans. Smooth the tops with a spatula. Bake in the preheated oven for 25-30 minutes, or until a toothpick inserted into the center comes out clean.

Once baked, remove the cakes from the oven and let them cool in the pans for 10 minutes. Then transfer to a wire rack to cool completely. This is key—don’t rush it!

While your cakes cool, let’s make the ganache. In a saucepan, heat heavy cream until it’s simmering. Pour it over chocolate chips in a bowl. Let it sit for a couple of minutes, then stir until smooth. Cool until slightly thickened, then it’s ready to pour over your cooled cakes.

Once the cakes are completely cool, place one layer on a serving plate. Pour a generous amount of ganache over the top, allowing it to drip down the sides. Place the second cake layer on top and repeat with more ganache. Use a spatula to create swirls or designs if desired.