Whisk the eggs, milk, melted butter and vanilla together in a bowl or jug.
In a second bowl, mix the flour and sugar.
Make a well in the flour mixture and pour the milk mixture into it.
Using your whisk, gradually incorporate flour into the milky mixture until you have a smooth batter.
Spoon a small ladleful of batter into the waffle maker. The batter will give 8 waffles in a standard waffle maker. Don't overfill your waffle iron as the batter will expand considerably as it cooks.
Cook for 3-5 minutes, depending on how well done you like your waffles.