Heat oven to 350 degrees F. Grease and flour 12-cup bundt pan.
In medium-size bowl, toss berries with the 1 tablespoon flour.
In clean, medium-size bowl, whisk together remaining 2-1/2 cups flour, baking powder and salt.
In large bowl, beat butter until smooth. Beat in sugar and vanilla until creamy, 2 minutes. Add egg whites; beat until smooth, 1 minute. On low speed, beat in flour in 2 additions alternately with yogurt. Fold in berries. Pour into prepared pan, spreading evenly; tap pan lightly on counter to release air bubbles.
Bake in 350 degree F oven until toothpick inserted in top comes out clean, 45 to 50 minutes. Let cool in pan on wire rack 10 minutes. Turn cake out onto rack; let cool completely.
In small bowl, stir together sugar and juice. Add water as needed for good drizzle consistency. Pour over cake. Let stand until set, 10 minutes. Fill center with blueberries, if desired. Cut into 16 slices to serve. Makes 16 servings.