Preheat oven to 350 degrees. Prepare a 9-inch springform pan with cooking spray.
Combine all the ingredients with a fork or a pastry blender until a thick crumb forms. Set aside.
In a small bowl, combine the cinnamon and sugar and set aside. Reserve 3/4 of cinnamon and sugar for the middle of the cake and the remainder to mix into the streusel.
In a large mixing bowl, add in the cake mix and dry pudding mix. Stir to combine.
Add in the sour cream, egg, vanilla, and butter. Beat with a hand mixer on medium until well combined.
Spread half the batter into the prepared pan.
Sprinkle 3/4 of the cinnamon sugar mixture over the cake.
Place remaining batter over the sugar mixture. You can do this in dollops as the batter will be very thick.
Sprinkle the blueberries on top of the cake batter. Don't mix.
Mix remaining cinnamon sugar into the streusel and cover the cake and blueberries with the streusel.
Bake cake for approx. 50 -60 min or until a toothpick comes out clean. Start checking the cake at 45 minutes because ovens vary. If streusel starts to brown cover with a piece of foil to prevent burning.
While the cake is baking make the glaze.
In a medium bowl, add in the powdered sugar, milk, and vanilla extract. Mix all together until the glaze is smooth and well incorporated.
Let the cake cool for around 15 minutes before removing from the pan. When cake cools completely Drizzle with the glaze