Ingredients:

  • 1/2 cup (60g) all-purpose flour
  • 1/2 cup (100g) light brown sugar, packed
  • 1 tbsp (8g) ground cinnamon
  • 4 tbsp (56g) unsalted butter, melted
  • 2 cups (240g) all-purpose flour
  • 1 tsp (4g) baking powder
  • 1/2 tsp (2g) baking soda
  • 1/2 tsp (3g) salt
  • 1/2 cup (115g) unsalted butter, softened
  • 3/4 cup (150g) granulated sugar
  • 2 large eggs
  • 1 tsp (5ml) vanilla extract
  • 1/2 cup (120g) full-fat sour cream
  • 2 cups (230g) grated zucchini, squeezed dry
  • 1 tsp (2g) ground cinnamon

Instructions:

  1. Whisk together the flour, brown sugar, and cinnamon in a small bowl. Pour in the melted butter and stir with a fork until the mixture forms sandy, mahogany-colored clumps. Set aside.
  2. In a large bowl, cream the softened butter and granulated sugar until pale and fluffy. Beat in the eggs one at a time, followed by the vanilla extract. Stir in the sour cream until the mixture is velvety and smooth.
  3. Whisk the dry ingredients (flour, baking powder, baking soda, salt, cinnamon) in a separate bowl. Gently fold the dry ingredients into the wet batter using a spatula—do not overmix. Fold in the squeezed, grated zucchini.
  4. Spread the batter evenly into a parchment-lined 9x9 inch baking pan and sprinkle the streusel generously over the top. Bake at 350°F (175°C) for 40-45 minutes, or until a toothpick inserted into the center comes out clean with just a few moist crumbs.