Preheat the waffle iron. For crispier waffles, choose a higher/darker setting.
If desired (to keep cooked waffles warm), preheat the oven to 200 degrees.
In a large bowl, whisk together the flour, sugar, baking powder, and salt.
In a separate bowl, whisk together the milk, melted butter, eggs, and vanilla.
Add the milk mixture to the flour mixture and mix until just combined, being careful not to over-mix.
Let the batter sit for 10 minutes.
Coat your waffle iron with cooking spray (or thin layer of neutral-flavored oil).
Spoon the batter onto the preheated waffle iron, until it’s within 1/2-inch of the edges. Depending on your waffle iron, this could be 1/3 to 3/4 cup of batter.
Cook until the waffle is golden brown on both sides. Some waffle irons will indicate when the waffle is ready, but if your waffle iron doesn’t have an indicator, check for doneness when the steam subsides.
If desired, keep cooked waffles warm, on a wire rack, in a 200-degree oven.
Serve warm with desired toppings.