Preheat oven to 350 degrees F. Spray 2 (9 by 5-inch) loaf pans with nonstick cooking spray and dust lightly with flour.
In a large mixing bowl combine all of cake ingredients. Mix on medium speed until well incorporated, about 3 minutes. Pour the batter into the prepared loaf pans. Bake until a toothpick inserted in the center comes out clean and the top is golden brown, about 40 to 50 minutes. Allow to cool for 5 minutes, then remove them from the pans and cool completely on a wire rack over a sheet pan.
Put the confectioners' sugar in a large bowl and slowly beat in the sparkling wine until consistency is thick but pourable. Pour the glaze over top of the cakes and allow it to drip down the sides. Let sit for 5 minutes to set before slicing and serving.