01 - Preheat oven to 350°F (175°C). Grease and line an 8-inch round cake pan with parchment paper.
02 - In a medium bowl, whisk together the all-purpose flour, matcha powder, baking powder, and salt until evenly distributed. Set aside.
03 - In a large mixing bowl, beat the unsalted butter and granulated sugar together using an electric mixer until light and fluffy, approximately 3 minutes.
04 - Add the eggs one at a time, mixing thoroughly after each addition. Stir in the vanilla extract until fully combined.
05 - Add half of the dry ingredient mixture to the wet ingredients and mix just until incorporated. Pour in the whole milk and mix gently. Fold in the remaining dry ingredients and mix until the batter is smooth and free of lumps.
06 - Pour the batter into the prepared cake pan and smooth the surface evenly with a spatula.
07 - Bake for 28 to 32 minutes, or until a toothpick inserted into the center of the cake comes out clean.
08 - Allow the cake to cool in the pan for 10 minutes, then turn it out onto a wire cooling rack to cool completely.
09 - Whisk together the powdered sugar and matcha powder, then dust evenly over the completely cooled cake before serving.