Ingredients:

  • 1/2 cup (60g) all-purpose flour
  • 1/2 cup (100g) brown sugar, packed
  • 1 tbsp (8g) ground cinnamon
  • 4 tbsp (57g) unsalted butter, cold and cubed
  • 1 1/2 cups (190g) all-purpose flour
  • 1 tsp (5g) baking powder
  • 1/2 tsp (3g) baking soda
  • 1/2 tsp (3g) salt
  • 1 tsp (2g) ground cinnamon
  • 1/2 cup (115g) unsalted butter, softened
  • 3/4 cup (150g) granulated sugar
  • 1 large egg (50g), room temperature
  • 1 tsp (5ml) vanilla extract
  • 1 cup (245g) plain Greek yogurt, room temperature
  • 2 cups (300g) Granny Smith or Honeycrisp apples, peeled and finely diced

Instructions:

  1. Preheat oven to 350°F (175°C). Grease a 9x9 inch pan and line it with parchment paper. In a small bowl, rub together the streusel ingredients (60g flour, 100g brown sugar, 8g cinnamon, 57g cold butter) with fingers until the mixture resembles coarse, sandy clumps; set aside.
  2. In a large bowl, beat the softened butter (115g) and granulated sugar (150g) with an electric mixer until light and fluffy. Add the egg (50g) and vanilla (5ml), beating until fully incorporated. Stir in the Greek yogurt (245g) until the batter is smooth and velvety.
  3. Whisk together the flour (190g), baking powder (5g), baking soda (3g), salt (3g), and cinnamon (2g). Gradually fold these dry ingredients into the wet batter using a spatula. Gently stir in the diced apples (300g).
  4. Pour the batter into the prepared pan and sprinkle the streusel evenly across the top. Bake for 40–45 minutes, or until a toothpick inserted into the center comes out clean and the top is mahogany-colored.