Ingredients:

  • 1/2 cup (100g) granulated sugar
  • 1/4 cup (30g) all-purpose flour
  • 1/4 cup (30g) packed light brown sugar
  • 1 teaspoon ground cinnamon
  • 1/4 cup (57g) cold unsalted butter, cut into small cubes
  • 2 cups (250g) all-purpose flour
  • 1 teaspoon baking powder
  • 1/2 teaspoon baking soda
  • 1/4 teaspoon salt
  • 1/2 cup (113g) unsalted butter, softened
  • 3/4 cup (150g) granulated sugar
  • 2 large eggs
  • 1 teaspoon vanilla extract
  • 1 cup (240ml) sour cream
  • 1 cup (120g) powdered sugar
  • 2-3 tablespoons milk
  • 1/2 teaspoon vanilla extract

Instructions:

  1. Prepare the Streusel: Combine dry streusel ingredients in a bowl. Cut in the cold butter until the mixture resembles coarse crumbs. Set aside.
  2. Prepare the Cake Batter: Whisk together dry cake ingredients (flour, baking powder, baking soda, salt) in a bowl.
  3. Cream Butter and Sugar: In a separate bowl, cream together softened butter and sugar until light and fluffy using an electric mixer.
  4. Incorporate Eggs and Vanilla: Beat in eggs one at a time, then stir in vanilla extract.
  5. Alternate Wet and Dry Ingredients: Gradually add the dry ingredients to the wet ingredients, alternating with the sour cream, beginning and ending with the dry ingredients. Mix until just combined. Do not overmix.
  6. Assemble the Cake: Pour half of the cake batter into the prepared baking pan. Sprinkle half of the streusel topping evenly over the batter. Pour the remaining batter over the streusel, then sprinkle with the remaining streusel topping.
  7. Bake: Bake in a preheated oven at 350°F (175°C) for 35-45 minutes, or until a wooden skewer inserted into the center comes out clean. Check for doneness around 35 minutes, as baking times may vary.
  8. Cool: Let the cake cool in the pan for 10 minutes before transferring it to a wire rack to cool completely.
  9. Prepare the Glaze: Whisk together powdered sugar, milk (or cream), and vanilla extract until smooth. Add more liquid if needed to achieve desired consistency.
  10. Glaze the Cake: Drizzle the glaze over the cooled cinnamon coffee cake.
  11. Serve: Cut into squares and serve.