Preheat the oven to 180°C (356°F).
In a bowl, mix together the flour, cocoa powder, baking powder, and sugar.
In another bowl, whisk together the eggs, milk, and melted butter.
Combine the dry and wet ingredients and mix until well incorporated.
Gently fold in the chocolate chips.
Divide the batter evenly into muffin tins.
Bake in the preheated oven for about 20 minutes.
Let the finished muffins cool.