Preparation: Preheat your oven to 350°F (175°C). Line a standard loaf pan meticulously with parchment paper, leaving an overhang on the sides for easy removal.

Mix the Dry Ingredients: In a medium bowl, sift together the all-purpose flour, matcha powder, and baking powder. Sifting is crucial to prevent green tea lumps in the final cake.

Cream Butter and Sugar: In a large mixing bowl, use a hand mixer to beat the perfectly softened butter and the sugar on medium-high speed for 3 to 4 minutes. It must become pale, light, and very fluffy to ensure a tender cake.

Add Eggs and Liquid: Add the room-temperature eggs one at a time, beating well after each addition to emulsify the batter. Pour in the whole milk and vanilla extract, mixing briefly.

Fold and Bake: Pour the green dry ingredients directly into the wet batter. Use a silicone spatula to gently and methodically fold the mixture from the bottom up until just combined. Do not overmix. Pour the thick batter into the loaf pan and smooth the top. Bake for 40 to 45 minutes until a toothpick inserted in the center comes out clean. Cool completely before slicing.