Preheat oven to 325°.
Coat an 8-inch square baking dish with cooking spray; dust with 1 tablespoon flour, tapping out excess. Set aside.
Blot cherries dry on paper towels. Combine cherries, cornstarch, 1 teaspoon vanilla, and almond extract in a small bowl; toss gently. Set aside.
Combine eggs, egg whites, and sugar in medium bowl, stirring with a whisk. Add 1/3 cup flour, yogurt, milk, and remaining teaspoon vanilla; stir with a wire whisk until smooth. Pour egg mixture slowly over cherries; do not stir. Bake at 325° for 50 minutes or until set and lightly browned. Sprinkle with sifted powdered sugar. Serve warm.