Preheat the oven to 180°C (356°F).
Sift flour, cocoa powder, and baking powder together.
In a bowl, combine eggs and sugar and mix well.
Add milk and melted butter, then mix.
Add the dry ingredients and mix until combined.
Stir in the chocolate chips.
Pour the batter into the pan.
Bake in the oven at 180°C (356°F) for 25 minutes.