Whole-Grain Blondies

Preheat oven to 350 degrees F. Line a 9-by-13-inch baking pan with parchment paper or foil, allowing it to slightly overhang opposite edges. Coat with cooking spray.

Melt butter in a large saucepan over medium heat. Cook, swirling often, until fragrant and starting to brown, 4 to 5 minutes. Remove from heat. Whisk in brown sugar; let cool for 15 minutes.

Whisk flour, baking powder and salt in a medium bowl.

Whisk eggs and vanilla into the cooled butter mixture until well combined. Add the flour mixture in 2 additions, gently folding until just combined. Evenly spread the batter into the prepared pan.

Bake the blondies until light brown around the edges, 18 to 22 minutes. They will appear slightly underbaked in the center, but will firm up as they cool. Let cool completely in the pan on a wire rack, about 2 hours. To cut, grab the overhanging parchment or foil and transfer the whole batch to a cutting board, then cut into 24 bars.