• Preheat oven to 350°F.
• Grease a 9-inch round deep cake pan and flour generously.

Make the Streusel

• In a medium bowl, whisk together flour, sugar, and salt.
• Stir in butter until the mixture is crumbly (using your hands works well).
• Stir in almonds. Set aside.

Prepare the Cake

• In the bowl of a stand mixer fitted with the paddle attachment, beat butter and sugar at medium-high speed until fluffy, 3 to 4 minutes, stopping to scrape the sides of the bowl, as necessary.
• Reduce mixer speed to low and add eggs, one at a time, beating well after each addition.
• Stir in the extracts.
• In a medium bowl, whisk together both types of flour, baking powder, and salt.
• Gradually add flour mixture to butter mixture alternately with milk, beginning and ending with flour mixture, beating just until combined after each addition.
• Stir in sour cream.
• Pour half of batter into prepared pan.
• Sprinkle with 1¼ cup blueberries, and top with the remaining batter, smoothing the top with a spatula.
• Top with remaining ¼ cup blueberries, and sprinkle with streusel and turbinado sugar.
• Bake until a toothpick, or wooden pick, inserted into the center comes out clean, 50 to 55 minutes.
• Let cool in pan for 15 minutes.
• Run a sharp knife around edges of cake to loosen sides.
• Invert onto a plate, and then invert again onto a serving plate. Serve at once, or cover, and let cool until ready to serve.