Ingredients:

  • 1/2 cup (65g) all-purpose flour
  • 1/3 cup (65g) light brown sugar, packed
  • 1 tsp (2g) ground cinnamon
  • 4 tbsp (55g) unsalted butter, chilled and cubed
  • 2 cups (250g) all-purpose flour
  • 1 tbsp (12g) baking powder
  • 1/2 tsp (3g) salt
  • 1/2 cup (115g) unsalted butter, softened
  • 3/4 cup (150g) granulated sugar
  • 2 large eggs, room temperature
  • 1 tsp (5ml) pure vanilla extract
  • 1 cup (240g) full-fat sour cream, room temperature
  • 2 cups (300g) fresh peaches, peeled and diced
  • 1 tbsp (8g) all-purpose flour
  • 1/2 tsp (1g) ground cinnamon

Instructions:

  1. In a medium bowl, whisk together 1/2 cup flour, 1/3 cup brown sugar, and 1 tsp cinnamon.
  2. Use a fork or fingertips to rub chilled butter into the dry ingredients until the mixture resembles coarse, sandy pebbles. Refrigerate until needed.
  3. Preheat oven to 350°F (175°C) and grease a 9x9 inch square baking pan.
  4. In a large bowl, cream softened butter and granulated sugar on medium-high for 3-5 minutes until pale and fluffy.
  5. Beat in eggs one at a time, then stir in vanilla extract until fully incorporated.
  6. Stir in room temperature sour cream until the mixture is smooth.
  7. Gradually fold in 2 cups flour, baking powder, and salt using a spatula. Mix only until no white streaks remain.
  8. In a small bowl, toss diced peaches with 1 tbsp flour and 1/2 tsp cinnamon to prevent sinking.
  9. Fold peaches into the batter and spread evenly into the prepared baking pan.
  10. Sprinkle the chilled cinnamon streusel over the top and bake for 45 minutes.