Preheat the Oven:
Begin by preheating your oven to 350°F (175°C). Grease a 9x13-inch baking pan, preparing it for the delightful chocolate creation ahead.
Make the Cake Batter:
In a spacious mixing bowl, combine the flour, sugar, dark cocoa powder, baking powder, baking soda, and salt. Next, incorporate the eggs, milk, vegetable oil, and vanilla extract, stirring until fully blended. Carefully add the boiling water; the batter will be thin, which is essential for achieving a moist cake.
Bake the Cake:
Pour the prepared batter into the greased pan, smoothing the surface for even baking. Place it in the oven and bake for 30 to 35 minutes, or until a toothpick inserted into the center comes out clean. Allow the cake to cool completely in the pan before applying the frosting.
Prepare the Frosting:
In a separate medium-sized bowl, beat the softened butter until it reaches a creamy consistency. Gradually mix in the dark cocoa powder, powdered sugar, milk, and vanilla extract, beating until the mixture is smooth and thick. Adjust the amount of milk as necessary to achieve your desired frosting consistency.
Frost the Cake:
Once the cake has cooled, generously spread the rich chocolate frosting over the top. The glossy, dark frosting will make this cake utterly irresistible.
Serve:
Cut the cake into generous squares and indulge in this decadent dark chocolate delight. It is truly a confection that chocolate lovers dream of—rich, fudgy, and utterly unforgettable.