Whisk together flour, baking powder, and salt in a bowl.
In a separate bowl, whisk together egg, sugar, milk, and oil.
Blend the dry ingredients into the wet mixture.
Lightly coat a waffle iron with cooking spray.
Ladle batter into the iron and cook for about 5-7 minutes.
Slice each waffle in half.
Spread pizza sauce onto a waffle half. Top with pepperoni slices, mozzarella, and another waffle half. Repeat with remaining ingredients.
Toast waffles until cheese is melted and cut into sticks.