Preheat oven to 325 degrees. Spray an 8" square baking pan with cooking spray. Line with parchment paper, leaving paper sticking up on two sides to help remove blondies from pan after baking. Spray parchment paper with non-stick spray and set aside.
In a large bowl whisk together flour, baking powder and salt until well combined. Set aside.
Add softened butter and brown sugar to the bowl of a stand mixer with the paddle attachment. Cream together about 5 minutes until light and fluffy. Add 2 eggs and vanilla and mix until thoroughly combined. Pour the dry ingredients into the bowl and mix until just combined. Pour mixture back into large bowl and wash the mixing bowl.
In the clean bowl, beat together softened cream cheese, sugar, butter, flour, matcha powder, 1 egg and vanilla, until smooth.
Spread ½ the blondie batter in the bottom of prepared pan and smooth evenly. Next spread ½ the cream cheese batter over top. Dollop remaining blondie and cream cheese batters randomly. Using a butter knife, swirl the batter together to create pattern.
Bake blondies for 45–50 minutes until only moist crumbs remain on tester. Remove from oven and place on rack. When cool, grab parchment paper handles and pull blondies out of pan. Slice and enjoy!
Elevate these blondies to the next level by adding 1 cup of white chocolate chips to the batter!