Ingredients:

  • 1 cup (225g) unsalted butter, melted and cooled
  • 1.5 cups (300g) light brown sugar, packed
  • 0.5 cup (100g) granulated sugar
  • 2 large eggs, room temperature
  • 1 tbsp vanilla bean paste
  • 2 cups (250g) all-purpose flour
  • 0.75 tsp kosher salt
  • 4 tbsp (56g) unsalted butter, very soft
  • 0.25 cup (50g) light brown sugar
  • 1.5 tbsp ground cinnamon
  • 4 oz (115g) full-fat cream cheese, softened
  • 2 tbsp (28g) unsalted butter, softened
  • 1 cup (120g) powdered sugar
  • 1.5 tbsp heavy cream
  • 1 pinch salt

Instructions:

  1. Preheat your oven to 350°F (180°C). Grease an 8x8 inch pan and line it with parchment paper as described above.
  2. In a large glass whisking bowl, combine the 1 cup melted butter with 1.5 cups light brown sugar and 0.5 cup granulated sugar. Whisk vigorously for at least 2 minutes until the mixture transitions from grainy to smooth.
  3. Add the 2 large eggs and vanilla bean paste. Whisk until the mixture is fully emulsified and slightly pale.
  4. Using a rubber spatula, gently fold in the 2 cups of all-purpose flour and 0.75 tsp kosher salt until just combined. Do not overmix.
  5. In a separate small bowl, mix 4 tbsp soft butter, 0.25 cup brown sugar, and 1.5 tbsp cinnamon until it forms a thick paste for the swirl.
  6. Spread two thirds of the blondie batter into the prepared pan. Drop dollops of the cinnamon mixture over the batter, then top with the remaining blondie batter. Use a butter knife to swirl the layers together until you see beautiful marbling.
  7. Bake for 25 minutes until the edges are golden brown and the top has a crackly, meringue-like appearance. Let cool completely in the pan.
  8. For the frosting, beat the 4 oz cream cheese and 2 tbsp butter until smooth. Gradually add 1 cup powdered sugar, heavy cream, and a pinch of salt. Whisk until silky.
  9. Spread the frosting over the cooled blondies, lift from the pan using the parchment overhang, and slice into 16 bars.