Preheat your oven to 350°F (175°C) and grease a 9-inch round cake pan with butter or cooking spray, then dust with flour.

In a large mixing bowl, sift together the flour, sugar, cocoa powder, baking powder, baking soda, and salt.

In another bowl, beat the softened butter until creamy. Gradually add sugar, beating until light and fluffy. Add eggs one at a time, mixing well after each addition. Stir in vanilla extract and buttermilk until combined.

Gradually add the dry ingredients to the wet mixture, alternating with boiling water, mixing until just combined. Gently fold in the chocolate chips.

Pour the batter into the prepared cake pan and smooth the top. Bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean. Let cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.

To make the ganache, heat the heavy cream in a saucepan until it simmers. Remove from heat and add the chopped chocolate and butter. Let sit for a few minutes, then stir until smooth.

Once the cake is completely cooled, pour the ganache over the top, allowing it to drip down the sides. Slice and serve.