Preheat the oven to 180°C (356°F).
Sift flour, cocoa powder, and baking powder together into a bowl.
Add eggs and sugar to a bowl and whisk until well combined.
Add milk and melted butter, mix thoroughly.
Add the dry ingredients and whisk to make the batter.
Pour the batter into a cake pan.
Bake in the oven for 25~30 minutes.
Let the cake cool completely, then cut into desired sizes.