- 1 cup (2 sticks) unsalted butter, melted, plus more for the pan
- 2 1/2 cups all-purpose flour, spooned and leveled
- 1 teaspoon baking powder
- 1/2 teaspoon kosher salt
- 1 1/2 cups packed light brown sugar
- 2 large eggs
- 1 teaspoon pure vanilla extract
- Heat oven to 350° F. Butter an 8-inch square baking pan. Line the pan with a piece of parchment paper, leaving an overhang on 2 sides; butter the parchment.
- In a medium bowl, whisk together the flour, baking powder, and salt; set aside.
- In a large bowl, whisk together the butter, brown sugar, eggs, and vanilla until smooth. Add the flour mixture and mix until just combined (do not overmix).
- Spread the batter in the prepared pan and bake until a toothpick inserted in the center comes out clean, 40 to 45 minutes. Let cool completely in the pan. Holding the paper overhang, lift out the blondies. Cut into 16 squares.