Preheat the waffle iron. In a medium bowl, whisk the eggs and then whisk in the milk. Set aside.
In a large bowl, whisk together the flour, baking powder, sugar and salt. Pour in the egg mixture and whisk to combine; lumps will remain. Pour in the butter and stir until combined. Do not overmix.
Ladle about 1/3 cup batter for every 4-inch square of the waffle iron and cook according to the manufacturer's directions. Repeat with the remaining batter.