1In a small bowl combine the flour, light brown sugar, and cinnamon. Set aside.
2In a medium bowl add the flour, light brown sugar, cinnamon, and salt. Mix and then add the diced butter. With your fingers press the butter and flour together until you get a crumbly mixture. Set aside.
3Preheat oven to 350°F.
4In a medium bowl combine the dry ingredients. Add the flour, baking powder, and salt. Whisk together and set aside.
5In a large bowl add the butter, granulated sugar, and light brown sugar. Beat for a couple minutes until light and fluffy.
6Add the eggs, one at a time, and mix until combined.
7Add the sour cream and vanilla and mix until combined.
8Add the dry ingredients to the wet ingredients and mix until just combined.
9To a greased 8x8 baking pan add half of the batter and spread it out evenly. Sprinkle all of the filling evenly. Add the rest of the batter and spread it out carefully and evenly. Sprinkle the crumble all over.
10Bake for 50-55min. Let it cool for about 30 minutes.