Red Currant Bakery

Cinnamon Sugar Crumble
0 In a medium bowl add in the flour and brown sugar, stir together with a fork. Add the cold cinnamon sugar butter in 1" cubes into the bowl.
2 Use your hands to rub the butter into the flour sugar mixture until fully combined.
3 Place the crumble in the fridge while you make the cake batter.
Blueberry Cake Batter
5 Preheat the oven to 350 F and place a rack in the center.
6 In a medium bowl add in the sugar, 150 grams of the flour, baking soda, baking powder, and salt and whisk to combine.
7 Add in the butter, greek yogurt, eggs, and vanilla.
8 Use the paddle attachment or a hand mixer to mix the ingredients first on medium low speed. Then increase the speed until just combined.
9 Add in the blueberries and the remaining 50 grams of flour. Use a flat rubber spatula to fold the blueberries and flour into the cake batter.
Bake
11 If not using a non-stick pan, spray the cake pan with your baking spray. Line with a rectangle of parchment that is 15" x 7" from one side to another.
12 Pour slightly more than half of the cake batter into the pan, sprinkle with half of the crumble. Then, dollop on the second half of the cake batter. Do your best to spread the cake batter over the streusel, careful not to mix in the crumble.
13 Sprinkle with the second half of the crumble. 
14 Place the cake into the preheated oven and bake for 30 minutes. Rotate the cake 180 degrees and bake for 25-30 more minutes.
15 The cake is done when the cake has puffed a bit and no longer wobbles.
16 Once baked, remove from the oven and leave to cool for at least 15-20 minutes on a wire rack. Run a knife along the edge between the cake and the pan. Then either lift the cake out with the parchment or slice the cake while it's still in the pan.