Ingredients:

  • ½ cup (113g) unsalted butter, cold and cubed
  • ⅔ cup (135g) all-purpose flour
  • ⅓ cup (67g) granulated sugar
  • ½ teaspoon ground cinnamon
  • ½ cup (113g) unsalted butter, softened
  • ¾ cup (150g) granulated sugar
  • 1 large egg
  • ½ cup (120ml) milk
  • 1 ½ cups (192g) all-purpose flour
  • 1 ¾ teaspoons baking powder
  • ¼ teaspoon salt
  • 2 cups (280g) fresh blueberries, lightly floured

Instructions:

  1. Prepare the Streusel: Combine flour, sugar, and cinnamon in a bowl. Cut in the cold butter using a pastry blender or your fingers until the mixture resembles coarse crumbs. Refrigerate while you prepare the cake.
  2. Cream Butter and Sugar: In a separate bowl, cream together the softened butter and sugar until light and fluffy.
  3. Add Egg and Milk: Beat in the egg until well combined. Gradually add the milk, mixing until just combined.
  4. Combine Dry Ingredients: In another bowl, whisk together the flour, baking powder, and salt.
  5. Combine Wet and Dry: Gradually add the dry ingredients to the wet ingredients, mixing until just combined. Do not overmix!
  6. Fold in Blueberries: Gently fold in the lightly floured blueberries. This prevents them from sinking to the bottom.
  7. Assemble and Bake: Pour the batter into the prepared baking pan. Sprinkle the streusel topping evenly over the batter. Bake in a preheated oven at 375°F (190°C) for 35-40 minutes, or until a toothpick inserted into the center comes out clean.
  8. Cool and Serve: Let the buckle cool in the pan for at least 15 minutes before cutting and serving.