Melt In Your Mouth Blueberry Cake

INGREDIENTS

• 1/2 cup butter
• 1/2 cup white sugar
• 1/4 teaspoon salt
• 1 teaspoon vanilla extract
• 2 egg yolks
• 1 1/2 cups all-purpose flour
• 1 teaspoon baking powder
• 1/3 cup milk
• 2 egg whites
• 1/4 cup white sugar
• 1 1/2 cups fresh blueberries
• 1 tablespoon all-purpose flour
• 1 tablespoon white sugar