01 -
Preheat oven to 350°F. Line an 8x8 square pan with foil and spray with non-stick spray. Set aside.
02 -
In a large bowl, whisk melted butter and brown sugar until smooth and combined (about one full minute). Whisk in the egg and vanilla extract. Sprinkle the flour, baking powder, and salt over the sugar mixture. Use a rubber spatula to stir until combined. Pour the batter into the prepared pan and spread into an even layer.
03 -
In a small saucepan over medium heat, melt butter and brown sugar. Cook, whisking frequently, until the sugar dissolves and the mixture is smooth. Remove from heat and stir in cinnamon and salt.
04 -
Dollop or drizzle the cinnamon mixture over the top of the blondie batter. Use the tip of a sharp knife to swirl it gently into the batter without reaching the bottom of the pan. Less swirling creates a more noticeable contrast. Use a figure-8 motion.
05 -
Bake for 21-24 minutes, until it puffs up slightly, the edges set and begin to brown, and the center still has a slight jiggle. Avoid overbaking. Cool completely on a wire rack.
06 -
Using a hand mixer or whisk, stir the cream cheese until smooth. Add powdered sugar, milk, and vanilla extract. Beat or whisk until fully combined. Adjust the consistency by adding more powdered sugar to thicken or more milk to thin.
07 -
Drizzle the cream cheese icing over the cooled blondies. Slice into bars and serve.