INGREDIENTS

Streusel:

1 cup light brown sugar

1/2 cup old fashioned rolled oats

1/3 cup all-purpose flour

1 cup walnuts, chopped

1 tablespoon ground cinnamon

6 tablespoons unsalted butter, softened

Cake:

12 tablespoons unsalted butter, softened (plus additional for skillet)

1 3/4 cup granulated sugar

3 large eggs, lightly beaten

1 1/2 cups sour cream

1/2 teaspoon almond extract

3 cups all-purpose flour

1 1/2 teaspoons baking powder

1/2 teaspoon baking soda

1/2 teaspoon salt

1 1/2 cups fresh blueberries

DIRECTIONS

1. Preheat the oven to 350°F. 

2. For the topping, combine the sugar, oats, flour, walnuts and cinnamon in a bowl. Add the butter and rub it into the sugar mixture until well combined and clumps form when pressed together. 

3. Generously butter the bottom and sides of an Enameled Cast Iron Skillet. 

4. Combine butter and sugar in the bowl of an electric mixer and beat on high speed with the paddle attachment until light and fluffy, 2-3 minutes. Whisk together the eggs, sour cream and almond extract in a bowl then add to the sugar mixture and beat on medium speed, stopping and scraping down the sides of the bowl occasionally, until combined. In a separate bowl combine the flour, baking powder, baking soda and salt. Add flour mixture to the sugar mixture and beat on low speed until just moistened, about 1-2 minutes. 

5. Spread half of the batter in the bottom of the prepared skillet. Top with a layer of the blueberries then sprinkle on 1/3 of the streusel mixture in an even layer. Spread the remaining batter over the filling. Sprinkle with the remaining streusel. 

6. Bake, rotating the pan every 15 minutes, until the cake is golden brown and a cake tester inserted into the center comes out clean, about 50-55 minutes. Let cool at least 20 minutes before cutting into wedges to serve.