In a large bowl, whisk together the flour, cornmeal, sugar, baking powder, baking soda, and salt. In a smaller bowl, whisk together the milk and eggs. You can whisk the eggs before adding or whatever. It also helps if these ingredients are room temperature for the next steps.
Add the wet ingredients to the dry, stirring until just combined. Stir in the melted butter until it’s all incorporated. Fold in the grated cheese. Let the batter sit for 10 minutes.
For any leftover flour and cornmeal, store them in a cool, dry place, away from heat. Best in an airtight container. Both will last in the pantry up to a year past the best by date this way. If you store them in the freezer, they can last more than 2 years past the best by date.
If you are ever wondering if your baking powder or baking soda are still fresh and ready to use, here are a few simple tests you can do. For baking powder, add a teaspoon of it to a cup of hot water. If it bubbles, it is still active. For baking soda, add 1 teaspoon of vinegar to 1 tablespoon of baking soda. If it bubbles, it is still active.
Eggs should last for a few months in the fridge, but you can easily test to see if they are good. Fill a tall glass with water, and carefully add the egg to the glass. If it stands on end or float, it is good as long as it is below the halfway mark of the glass. If it floats past that, toss it.
Heat your waffle iron to a medium-high setting.
When the waffle iron is ready, spray the iron with cooking spray, then pour about ¾ cup of batter at the center of the iron. This may vary depending on the size of your iron. Cook until crispy.