• Pre-Heat Oven to 350 degrees. • In a large mixing bowl add butter, brown sugar, sugar, cinnamon and flour. Mix with clean hands until the mixture is well combined and crumbly in texture. • In a mixer, add the butter (room temperature) and sugar, mix at a high speed for 30 seconds. • Add sour cream, vanilla, eggs, and mix. Scrape sides of the bowl and mix for 20 seconds. • Add ½ of the dry ingredients to the wet ingredients and mix until incorporated. • Add the rest of the dry ingredients to the mixture; do not over mix. • Spray your baking dish with non-stick spray, pour batter into dish, and spread evenly • Sprinkle the entire crumb mixture over the batter, covering it completely and evenly. • Bake for about 50 to 60 minutes. Allow to completely cool before cutting into 2-inch squares and sprinkle with powdered sugar.