In a large mixing bowl, whisk together the all-purpose flour, cornstarch, granulated sugar, baking powder, and salt until well combined.
In another bowl, combine the milk, eggs, melted butter or oil, and vanilla extract. Beat until smooth and creamy.
Pour the wet mixture into the dry ingredients. Gently fold together until just combined; a few lumps are fine.
Preheat your waffle iron according to the manufacturer's instructions and lightly grease if necessary.
Using a ladle, pour about ¾ cup of batter onto the preheated waffle iron. Cook according to your machine's instructions, generally around 4-5 minutes.
Carefully remove the waffles and serve immediately with your favorite toppings.
