Preheat oven to 325 degrees Fahreinheit. Melt the butter in the microwave and let cool to room temperature.
In a bowl, beat the sugar, butter and eggs together. In another bowl, sift together flour, baking powder and matcha powder.
Mix the dry and wet ingredient together. Mix in the white chocolate chips and adjust quantity to taste.
Put the mixture in a square baking pan lined with parchment paper. Bake the brownies for 27 minutes, or until fully cooked. Using a toothpick, check if the brownies are cooked thoroughly by sticking the toothpick at the center. If toothpick comes out clean, it's ready!
Let brownie cool for about 20 minutes before serving.