Preheat oven to 350F. Lightly spray the sides of an 8-inch springform pan with baking spray, line the bottom with parchment paper.
Mix the streusel topping by combining the flour and sugars in a bowl, then add the cubed butter. Use a pastry blender, fork, or your hands to cut the butter into the dry ingredients until coarse crumbs form. Place the streusel in the fridge while you mix the cake.
¼ cup sugar, ¼ cup dark brown sugar, ½ cup flour, 4 tablespoons butter
In a medium bowl, toss the blueberries with the 2 tablespoons flour, 2 teaspoons sugar and dash of cinnamon. Set aside.
1 ½ cup blueberries, 2 tablespoons flour, Dash cinnamon, 2 teaspoons sugar
In a medium to large mixing bowl, add the sugar, butter, and fresh lemon zest. Cream with a hand mixer on medium speed until light and fluffy, about 2 to 3 minutes.
½ cup butter, ½ cup granulated sugar, 1 tablespoon lemon zest
Add the sour cream, eggs and vanilla. Mix on low speed until mostly combined.
1 cup sour cream, 2 eggs, ½ teaspoon vanilla extract
In a separate bowl, combine flour and baking soda with a whisk. Add to the bowl of batter and stir with a spoon or spatula until just combined. The batter will be quite thick.
1 ½ cup flour, ¾ teaspoon baking soda
Add the prepared blueberries, including the extra flour and sugar in the bowl. Fold in until just combined.
Pour the batter into the prepared pan and top with the streusel topping.
Bake for 45 to 50 minutes or until the top is golden brown and a toothpick inserted in the center comes out clean.
Cool the cake on a wire rack. Remove the outer ring of the pan and move the cake to a serving plate. Stir together the powdered sugar and lemon juice to make the glaze. Drizzle the glaze over the top of the coffee cake.
¾ cup powdered sugar, 1 ½ tablespoon lemon juice
Slice and serve!