In a large bowl, whisk together flour, baking powder, salt, matcha, and sugar until well combined.
In a separate bowl, whisk together the melted butter, milk, and vanilla extract until smooth. Fold the dry flour mixture into the wet ingredients, mixing until just combined.
Cover the bowl and refrigerate the batter for 2 hours. This will help the madeleines hold their shape during baking.
When ready to bake, preheat your oven to 350°F.
Grease and flour your madeleine molds to prevent sticking.
Fill each mold about 3/4 of the way full with the batter. Bake in the preheated oven for 13-15 minutes.
Let the madeleines rest in the pan until they are cool to the touch. Then, gently remove them and place them on a wire rack to finish cooling completely.
Once the madeleines are fully cooled, dust them with matcha powdered sugar using a sifter. Serve and enjoy your matcha madeleines!