Preheat the oven to 180°C (356°F).
In a bowl, mix together flour, matcha powder, and baking powder.
In a separate bowl, cream the butter and sugar.
Add eggs one at a time, mixing well after each addition.
Pour in the milk and mix, then gently fold in the dry ingredients.
Spoon the batter into cupcake molds.
Bake at 180°C (356°F) for 20–25 minutes.
Cool, then decorate or ice as desired.