Preheat your oven to 350°F (175°C) and line a cupcake pan with liners.
In a large bowl, whisk together the flour, sugar, cocoa powder, baking powder, baking soda, and salt.
Add the eggs, milk, oil, and vanilla extract to the dry ingredients and mix until well combined.
Stir in the cooled coffee until the batter is smooth.
Fill each cupcake liner halfway with batter, add a teaspoon of Nutella in the center, then top with more batter until ¾ full.
Bake for 18-20 minutes or until a toothpick inserted into the center comes out clean.
Let the cupcakes cool completely before topping with more Nutella.