In a large bowl whisk together the eggs, milk, and vanilla. Whisk until combined.
In a medium bowl combine the baking powder, sugar, salt, cinnamon, and flour.
Add the flour mixture to the egg mixture and whisk until mostly smooth. Whisk in the butter.
Fold in the blueberries.
Heat a waffle iron. Pour 1/3 cup of batter into the waffle iron and close it. Cook for 3-4 minutes or until the indicator light turns off to signal the waffle is finished.