Ingredients:

  • 375g all-purpose flour
  • 400g granulated sugar
  • 12g baking powder
  • 3g kosher salt
  • 225g unsalted butter, softened
  • 4 large eggs, room temperature
  • 240g full-fat sour cream
  • 10ml pure vanilla extract
  • 150g light brown sugar, packed
  • 15g ground cinnamon
  • 1g ground nutmeg
  • 240g powdered sugar, sifted
  • 45ml whole milk
  • 5ml vanilla extract

Instructions:

  1. Preheat your oven to 325°F (165°C). Lightly grease a 9x13-inch baking pan with butter and a dusting of flour.
  2. In a small bowl, whisk together the brown sugar, cinnamon, and nutmeg for the cinnamon swirl and set aside.
  3. In a stand mixer, cream the softened butter and granulated sugar together on medium-high for 3–5 minutes until pale and fluffy.
  4. Add eggs one at a time, beating well after each addition to maintain the emulsion. Mix in the 10ml vanilla extract and sour cream until combined.
  5. Gradually add the flour, baking powder, and salt to the wet ingredients. Mix on low speed until just combined, being careful not to overwork the gluten.
  6. Spread half of the batter into the prepared pan. Sprinkle the cinnamon sugar mixture evenly over the batter. Spread the remaining batter on top and use a knife to gently swirl the layers. Stop after 3-4 loops to keep the layers distinct.
  7. Bake for 40 minutes or until a toothpick inserted into the center comes out clean.
  8. While the cake is baking, whisk the powdered sugar, milk, and 5ml vanilla extract to create the glaze. Pour the glaze over the cake immediately while it is still piping hot to create the signature crackle finish.