Preheat the oven to 350ºF. Prepare two 9-inch cake pans by coating with baking spray or buttering and lightly flouring.
Add the flour, sugar, cocoa, baking powder, baking soda, salt and espresso powder to a large bowl or the bowl of a stand mixer. Whisk through to combine or, using the paddle attachment of the mixer, stir through the flour mixture until well combined.
Add the milk, vegetable oil, eggs, and vanilla to the flour mixture and mix together on medium speed until well combined. Reduce the speed and carefully add the boiling water until the batter is thoroughly mixed.
Distribute the cake batter evenly between the two prepared cake pans. Bake for 30-35 minutes, or until a toothpick or cake tester inserted in the center of the cake comes out clean.
Remove from the oven and allow to cool for about 10 minutes, remove from the pan and cool completely. Frost as desired.