Preheat 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 mixing bowl, sift together the dry ingredients: flour, sugar, cocoa powder, baking powder, baking soda, and salt.

Add the wet ingredients: milk, vegetable oil, eggs, and vanilla extract to the dry ingredients and mix until just combined.

Carefully stir in the boiling water to create a thin but smooth batter.

Divide the batter evenly between the prepared cake pans.

Bake for 25-30 minutes, or until a toothpick inserted into the center comes out clean.

Let the cakes cool in the pans for about 10 minutes before transferring to a wire rack to cool completely.