Step 1

Preheat oven to 200˚F. Set a wire rack inside a large rimmed baking sheet. Preheat waffle iron according to manufacturer's instructions. Process eggs in a blender until frothy, about 15 seconds. Add buttermilk and melted butter. Pulse until combined, about 10 pulses. Add flour, cornmeal, sugar, baking powder, baking soda, and salt. Pulse until fully combined, about 5 pulses, stopping to scrape down sides of blender as needed.

Step 2

Lightly coat hot waffle iron with cooking spray. Pour about ¼ cup batter per waffle in center of waffle iron. Cover with lid, and cook until golden brown, 4 to 5 minutes. Carefully remove waffle from waffle iron, and place on prepared baking sheet. Transfer to preheated oven to keep warm. Repeat process with remaining batter, letting waffle iron reheat and recoating it with cooking spray in between batches.