Begin by setting your oven to 350°F (175°C) and prepare two 9-inch round cake pans by greasing and dusting them with flour.

In a large bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt until well combined.

Incorporate the eggs, milk, vegetable oil, and vanilla into the dry mixture. Beat the mixture on medium speed for about 2 minutes until it is smooth and well blended.

Gradually mix in the boiling water, being cautious as the batter will be quite thin. Divide the batter evenly between the two prepared pans.

Bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean. Let the cakes cool in the pans for 10 minutes, then transfer them to wire racks to cool completely.

While the cakes cool, prepare the frosting by creaming the softened butter in a large bowl. Slowly add the powdered sugar and cocoa powder, mixing until smooth. Then, add the heavy cream and vanilla extract, beating until the frosting is light and fluffy.

Once the cakes have cooled, place one layer on a serving platter and generously spread frosting over the top. Stack the second layer on top and frost the entire cake, including the sides.

For the ganache, heat the heavy cream in a small saucepan until it just begins to simmer. Remove from heat and add the chocolate chips, letting them sit for a few minutes before stirring until the mixture is silky and smooth.

Pour the ganache over the frosted cake, allowing it to cascade down the sides for a beautiful finish.

Refrigerate the cake for at least 30 minutes to allow the ganache to set before slicing and serving.