Ingredients:

  • 3 cups (450g) Granny Smith apples, peeled and diced
  • 2 tbsp (30ml) lemon juice
  • 1 tsp (2g) ground cinnamon
  • 2 tbsp (25g) granulated sugar
  • 1 tbsp (8g) all-purpose flour
  • 1/2 cup (65g) all-purpose flour
  • 1/2 cup (100g) packed light brown sugar
  • 1 tsp (2g) ground cinnamon
  • 4 tbsp (56g) unsalted butter, cold and cubed
  • 2 cups (250g) all-purpose flour
  • 1 tbsp (12g) baking powder
  • 1/2 tsp (3g) salt
  • 1/2 cup (113g) unsalted butter, softened
  • 1 cup (200g) granulated sugar
  • 2 large eggs
  • 1 tsp (5ml) vanilla extract
  • 1 cup (240g) full-fat sour cream

Instructions:

  1. Preheat your oven to 350°F (175°C). Grease an 8-inch square baking pan and line the bottom with parchment paper.
  2. In a medium bowl, toss the diced apples with lemon juice, cinnamon, sugar, and flour until evenly coated.
  3. Cream together the softened butter and granulated sugar using an electric mixer until pale and fluffy. Beat in the eggs one at a time, then stir in the vanilla extract and sour cream until smooth.
  4. Whisk the flour, baking powder, and salt together in a separate bowl. Gently fold the dry ingredients into the wet batter using a spatula until no streaks of flour remain.
  5. Spread half of the batter into the prepared pan. Evenly distribute the apple mixture over the batter, then top with the remaining batter, smoothing it with a spatula.
  6. Rub the cold butter into the streusel ingredients (flour, brown sugar, cinnamon) with your fingers until crumbly, then sprinkle generously over the top.
  7. Bake for 50–55 minutes, or until a tester inserted into the center comes out clean and the top is a deep golden brown.