1. Preheat your oven to 350°F and grease two 9-inch round cake pans. Line the bottoms with parchment paper for easy removal.
2. In a large mixing bowl, combine the flour, sugar, cocoa powder, baking powder, baking soda, and salt. Whisk these dry ingredients together until well blended.
3. In a separate bowl, beat the eggs, then add in the milk, vegetable oil, and vanilla extract. Stir until the mixture is smooth and uniform.
4. Gradually add the wet ingredients to the dry ingredients, mixing until just combined. Be careful not to overmix, as this can lead to a dense cake.
5. In a small bowl, dissolve the espresso powder in the boiling water. Add this to the batter and stir until well incorporated. If desired, add a few drops of black food coloring to achieve a deeper hue.
6. Divide the batter evenly between the prepared cake pans. Bake for 30-35 minutes, or until a toothpick inserted into the center comes out clean.
7. Allow the cakes to cool in the pans for about 10 minutes, then transfer them to a wire rack to cool completely before frosting.

A little tip from my kitchen: when adding the espresso, I like to remind my daughters of the time I first learned about this secret ingredient from an Italian pastry chef during my travels. It’s these little stories that make baking such a heartfelt experience.