Step 1: Preheat the Oven

Start by preheating your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans to prevent the cake from sticking. If you have parchment paper, you can line the bottom of the pans for an even easier release after baking.

Step 2: Prepare the Cake Batter

In a medium bowl, whisk together the flour, cocoa powder, baking powder, baking soda, and salt. Set it aside.

In a separate large bowl, beat together the sugar, eggs, and oil until the mixture becomes light and fluffy. Add in the vanilla extract and mint extract. Gradually mix in the dry ingredients, alternating with the buttermilk. Once everything is combined, add the hot water and beat the batter for a few more seconds to ensure a smooth, runny consistency.

Step 3: Bake the Cake

Pour the batter evenly into the prepared cake pans. Place them in the oven and bake for 30-35 minutes, or until a toothpick inserted into the center of the cakes comes out clean. Once done, remove the cakes from the oven and let them cool in the pans for 10 minutes. Then, transfer the cakes onto a cooling rack to cool completely.

Step 4: Make the Mint Frosting

While the cakes are cooling, prepare the mint frosting. In a large mixing bowl, beat the softened butter until smooth and creamy. Gradually add powdered sugar, one cup at a time, and beat until well combined. Add mint extract, milk, and a few drops of green food coloring (if desired). Adjust the frosting consistency with more milk or powdered sugar until you achieve a smooth, spreadable texture.

Step 5: Assemble the Cake

Once the cakes are completely cool, place one layer on a serving plate. Spread a generous layer of mint frosting over the top. Add the second cake layer and frost the entire cake with the remaining mint frosting.

Step 6: (Optional) Add the Chocolate Ganache

For an extra indulgent touch, prepare a chocolate ganache. In a microwave-safe bowl, heat the heavy cream until it begins to simmer. Pour it over the chopped semi-sweet chocolate and let it sit for 5 minutes. Stir the mixture until smooth. Drizzle the ganache over the frosted cake for a glossy, rich finish.

Step 7: Serve and Enjoy

Allow the cake to set for about 30 minutes to let the frosting firm up. Then slice and serve your delicious Chocolate Mint Cake with a cup of tea or coffee.