Blueberry Crumb Cake

Recipe
Adapted from SmittenKitchen

Ingredients:
Butter for greasing pan

For the blueberry filling:
1/2 pound blueberries
2 tablespoons sugar
2 teaspoons cornstarch
zest of 1 lemon

For the crumbs:
1/3 cup dark brown sugar
1/3 cup granulated sugar
1 teaspoon ground cinnamon
1/2 teaspoon ground ginger
1/8 teaspoon salt
1/2 cup (1 stick or 4 ounces) butter, melted
1 3/4 cups cake flour

For the cake:
1/3 cup sour cream
1 large egg
1 large egg yolk
2 teaspoons vanilla extract
1 cup cake flour
1/2 cup sugar
1/2 teaspoon baking soda
1/2 teaspoon baking powder
1/4 teaspoon salt
6 tablespoons softened butter, cut into 8 pieces


Directions:
1. Preheat oven to 325 degrees. Grease an 8-inch-square baking pan. For filling, toss blueberries with sugar, cornstarch and lemon zest. Set aside.

2. To make crumbs in a large bowl, whisk sugars, spices and salt into melted butter until smooth. Then, add flour with a spatula or wooden spoon. It will look and feel like a solid dough. Leave it pressed together in the bottom of the bowl and set aside.

3. To prepare cake, in a small bowl, stir together the sour cream, egg, egg yolk and vanilla. Using a mixer fitted with paddle attachment, mix together flour, sugar, baking soda, baking powder and salt. Add butter and a spoonful of sour cream mixture and mix on medium speed until flour is moistened. Increase speed and beat for 30 seconds. Add remaining sour cream mixture in two batches, beating for 20 seconds after each addition, and scraping down the sides of bowl with a spatula. Scoop out about 1/2 cup batter and set aside.

4. Scrape remaining batter into prepared pan. Spoon blueberries over batter. Dollop set-aside batter over blueberries; it does not have to be even.

5. Using your fingers, break topping mixture into big crumbs, about 1/2 inch to 3/4 inch in size. They do not have to be uniform, but make sure most are around that size. Sprinkle over cake. Bake cake until a toothpick inserted into center comes out clean of batter 45 to 55 minutes. Cool completely before serving.

The recipe and image were copied directly from sugarcooking