Whisk together flour, baking powder, baking soda, and salt in mixing bowl. In large measuring cup or bowl add milk, eggs, oil, and vanilla whisk until smooth. Add wet ingredients to dry, whisk until batter is smooth, making sure there are no flour lumps. Ladle batter into preheated waffle iron, bake until done, remove to cooling rack, when completely cooled, place on a baking sheet in freezer until frozen solid, then store in Zip-loc freezer bags.