Preheat your oven to 350°F (175°C).

Grease an 8” round cake pan with melted butter and line the bottom with a round piece of parchment paper, also brushing the parchment paper with melted butter. Set aside.

In a large mixing bowl, combine coffee and buttermilk, followed by mixing in the vegetable oil, egg, and vanilla. Beat until well blended.

In a separate bowl, sift together the flour, cocoa powder, baking soda, and baking powder. Add salt and sugar to the dry mixture and whisk until a smooth batter forms.

Pour the cake batter into the prepared cake pan and bake for 30 to 35 minutes, or until a toothpick inserted into the center comes out clean with just a few crumbs attached.

Allow the cake to cool in the pan for 10 to 15 minutes before inverting it onto a wire rack to cool completely.

To prepare the chocolate ganache, heat the cream in a microwave-safe bowl for 50 to 55 seconds, watching carefully to prevent boiling over.

Place the chocolate in a separate mixing bowl and pour the hot cream over it. Let it sit for a minute or two before whisking until the chocolate is completely melted and the mixture is smooth. Allow the ganache to cool completely, then refrigerate for 15 to 20 minutes until it thickens but remains pourable.

Transfer the cooled cake onto a cake stand or plate, then drizzle the ganache over the top. Lightly tap the stand or plate on a tabletop to even out the ganache. Serve immediately or refrigerate the cake to further thicken the ganache before serving.