Servings: 12

Cake: subheading: Cake:
2 cups all-purpose flour 2 cups all-purpose flour
1 teaspoon baking powder 1 teaspoon baking powder
1 teaspoon baking soda 1 teaspoon baking soda
½ teaspoon salt ½ teaspoon salt
1 cup unsalted butter room temperature 1 cup unsalted butter room temperature
1 cup granulated sugar 1 cup granulated sugar
½ cup packed light brown sugar ½ cup packed light brown sugar
1 large egg 1 large egg
1½ teaspoons pure vanilla extract 1½ teaspoons pure vanilla extract
1 cup sour cream 1 cup sour cream
2 cups fresh blueberries 2 cups fresh blueberries
Crumb Topping: subheading: Crumb Topping:
⅓ cup packed light brown sugar ⅓ cup packed light brown sugar
⅔ cup all-purpose flour ⅔ cup all-purpose flour
1 tablespoon granulated sugar 1 tablespoon granulated sugar
¼ cup butter chilled ¼ cup butter chilled

Preheat oven to 350 degrees and butter a 9-inch square pan or line it with parchment paper.
Cake: subheading: Cake:
In a medium bowl, whisk together the 2 cups of flour, baking powder, baking soda, and salt.
In a mixing bowl, cream the butter. Add both sugars and beat until light and fluffy, about 3 minutes.
Add egg and vanilla and mix until combined.
Add half the dry ingredients and mix until just barely combined. Add half the sour cream and mix until barely combined. Add remaining flour, mix, and then remaining sour cream. Mix until smooth.
Pour batter into the prepared cake pan.
Sprinkle the blueberries evenly over the top. Gently press them down into the batter so that they're slightly embedded.
Crumb Topping: subheading: Crumb Topping:
in a medium bowl, mix together the flour and both sugars. Add the chilled butter and with a pastry cutter or two forks, mix until a coarse meal is formed.
Sprinkle the crumb topping over the blueberries.
Bake 40 to 50 minutes or until a toothpick inserted into the middle of the cake comes out clean. Cool before serving.