Ingredients:

  • 1/2 cup (60g) all-purpose flour
  • 1/2 cup (100g) brown sugar, packed
  • 1 tsp (2g) ground cinnamon
  • 4 tbsp (55g) cold unsalted butter, cubed
  • 1 1/2 cups (190g) all-purpose flour
  • 1 cup (200g) granulated sugar
  • 2 tsp (10g) baking powder
  • 1/2 tsp (3g) salt
  • 1/2 cup (115g) unsalted butter, softened
  • 1 large egg
  • 1/2 cup (120ml) buttermilk
  • 1 tsp (5ml) vanilla extract
  • 1 1/2 cups (225g) fresh blueberries
  • 1 tbsp all-purpose flour (for tossing berries)
  • 1 cup (120g) powdered sugar
  • 2 tbsp (30ml) fresh lemon juice
  • 1 tsp (5ml) lemon zest

Instructions:

  1. Preheat your oven to 350°F (175°C) and line an 8x8 inch square baking pan with parchment paper.
  2. In a large bowl, cream the softened butter and granulated sugar until the mixture looks pale and fluffy.
  3. Beat in the egg and vanilla extract.
  4. Whisk the flour, baking powder, and salt in a separate small bowl, then add them to the wet ingredients.
  5. Slowly stir in the buttermilk until just combined.
  6. Toss fresh blueberries in a tablespoon of flour, then gently fold them into the batter using a spatula until no streaks of flour remain.
  7. Pour the batter into the prepared pan and smooth the top.
  8. Combine the streusel ingredients (60g flour, 100g brown sugar, 2g cinnamon, and 55g cold cubed butter) and sprinkle evenly across the top of the batter.
  9. Bake for 35–40 minutes until the edges pull away slightly from the pan and the center springs back when touched.
  10. Allow the cake to cool for 10 minutes.
  11. Whisk powdered sugar, lemon juice, and lemon zest to create a glaze, then drizzle it over the cooled cake.