Preheat the oven to 180°C.
Melt unsalted butter over medium heat and let it cool.
In a bowl, mix egg whites and sugar together.
Add sifted cake flour, almond powder, and green tea powder, then mix.
Pour in the cooled butter and mix evenly.
Pour the batter into financier molds.
Bake in the oven at 180°C for 15 minutes.