1. Preheat oven to 350°.
2. Line a 9-inch square baking pan with parchment paper; coat with cooking spray.
3. Weigh or lightly spoon flour into dry measuring cups; level with a knife. Combine flour, 1 cup sugar, unsweetened cocoa, baking powder, and salt in a large bowl; stir with a whisk. Combine cherry preserves, 1/3 cup water, and butter in a small saucepan; bring to a boil. Add preserves mixture to flour mixture; stir well. Add egg and egg white; stir until smooth. Stir in semisweet chocolate chips. Scrape batter into prepared pan. Bake at 350° for 25 minutes or until a wooden pick inserted in center comes out with a few moist crumbs. Cool in pan on wire rack. Garnish with powdered sugar, if desired.
Lining the pan with parchment paper helps prevent the moist brownies from sticking.