01 - Preheat oven to 350°F. Line a 9x13-inch baking pan with parchment paper, allowing a slight overhang for easy removal.
02 - In a medium saucepan, melt the butter over medium heat. Continue cooking, swirling often, until the butter takes on a golden brown color and emits a nutty aroma, about 5 minutes. Transfer to a large mixing bowl and cool slightly.
03 - Add the brown sugar to the browned butter and whisk until smooth. Incorporate eggs one at a time, whisking well after each addition. Stir in vanilla extract.
04 - Sift together flour, baking powder, and fine sea salt. Fold the flour mixture gently into the wet mixture until just combined.
05 - Gently fold in chopped cherries until evenly distributed.
06 - Spread batter evenly into prepared pan. Sprinkle flaky sea salt across the surface.
07 - Bake for 25 to 30 minutes, until the edges turn golden and a toothpick inserted in the center comes out mostly clean with a few moist crumbs.
08 - Allow blondies to cool completely in the pan before lifting out and cutting into squares.