Preheat a waffle iron according to the manufacturer’s instructions.

Add the oats, baking powder, and salt to a food processor and pulse until the oats are finely ground into a flour-like texture.

Add the eggs, milk, and melted butter to the food processor with the oat mixture and blend until well combined. Let the batter sit for 10 minutes to thicken.

Spray the hot waffle iron with cooking spray, then add ⅓ cup of the batter to the iron. Close the iron and cook until the waffles are golden brown and crisp, about 5-6 minutes. Then remove the waffles to a wire rack and repeat with the remaining batter.

Serve warm, topped with butter, fresh fruit, and maple syrup, if desired.