Follow these steps to create the Dark Chocolate Whiskey Cake with Whiskey Ganache:

1. Preheat Oven: Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans.
2. Mix Dry Ingredients: In a large bowl, whisk together the flour, cocoa powder, sugar, baking powder, baking soda, and salt until well combined.
3. Combine Wet Ingredients: In a separate bowl, mix the melted butter, buttermilk, eggs, vanilla extract, and whiskey until combined.
4. Combine Mixtures: Slowly add the wet ingredients to the dry ingredients, mixing until just combined. Avoid overmixing; a few lumps are okay.
5. Divide Batter: Pour the batter evenly into the prepared cake pans.
6. Bake: Place the pans in the preheated oven and bake for 30-40 minutes, or until a toothpick inserted into the center comes out clean.
7. Cool: Remove from the oven and allow to cool in the pans for 20 minutes before transferring to wire racks to cool completely.
8. Prepare Ganache: In a small saucepan, heat the heavy cream over medium heat until just simmering. Pour it over the chopped semi-sweet chocolate in a bowl. Let it sit for 3-5 minutes to melt the chocolate, then stir until smooth.
9. Drizzle Ganache: Once the cakes are cooled, place one layer on a serving plate. Pour half of the ganache over the first layer, spreading it evenly. Top with the second layer and drizzle the remaining ganache on top.
10. Set Ganache: Allow the ganache to set at room temperature for about 30 minutes before slicing.

These straightforward steps will help you create a scrumptious Dark Chocolate Whiskey Cake with Whiskey Ganache that’s sure to wow your guests!