Combine the flour, baking powder and salt in a medium bowl. Set aside. Place the eggs, milk, bananas and butter into the Vitamix and secure the lid. Select variable 1. Turn the machine on and slowly increase the speed to variable 6. Blend for 20-30 seconds. Stop the machine and add the flour mixture. Secure the lid. Select variable 1 and slowly increase the speed to variable 6, blending for 20-30 seconds. Let the batter sit for 5-10 minutes. Preheat a waffle iron. Pour the batter into the preheated waffle iron and cook under the waffle maker indicates they are ready.