Using a whisk combine the flour, sugar, baking soda and salt in a large mixing bowl, then add the milk, baking powder, eggs and oil and whisk until is just combined, than stir in the banana and walnuts and let the mixture rest for about 5 min before using it.
Preheat the waffle maker to the desired setting.
Pour 2 cups of the mixture in the center of the lower grid of the preheated waffle maker and spread evenly, than close the lid. When ready carefully remove the waffles and repeat with the remaining mixture. For best results, serve immediately.
