Berry Pound Cake With Whipped Cream

Name: Berry Pound Cake With Whipped Cream
Ingredients: 1 cup (2 sticks) unsalted butter, softened, plus more for pans; 2 3/4 cups all-purpose flour; 1/2 cup cake flour (not self-rising); 1 tablespoon baking powder; 1 teaspoon salt; 2 1/4 cups granulated sugar; 1 1/2 teaspoons pure vanilla extract; 3 large eggs, plus 1 large egg white; 1 cup whole milk; 1 1/2 cups heavy cream; 1 tablespoon confectioners' sugar; 1 cup (about 4 ounces) fresh blueberries; 1 cup (about 4 ounces) fresh raspberries