Preheat oven to 400°F. Line baking sheet with parchment paper. Place bacon on parchment sheet and bake for 20-25 minutes, or until crispy. Set on paper towel-lined plate and reserve bacon fat.
Reduce oven to 200°F. In a large bowl, combine the flour, sugar, salt and baking powder. In another bowl, whisk to combine the egg yolks, buttermilk, butter and bacon fat. Set aside.
In a medium bowl, use a hand mixer to whip the egg whites to soft peaks. Set aside.
Pour the egg yolk mixture into the dry ingredients and stir until almost combined. Add the bacon, cheese and scallions and fold in. Finally, gently fold in the egg whites until just combined.
Preheat a waffle iron and spray with non-stick cooking spray. Add 1 cup of waffle mixture and cook to waffle iron's instructions. (About 5 minutes for me). When waffle is done place on wire rack in oven to keep warm. Repeat with remaining batter. Serve with some more chopped scallions and maple syrup. Enjoy!
Notes
Waffle Maker: Using a good waffle maker is half the battle. You will want a cast iron on non-stick model. If it has a done indicator, even better.
Fat Ratio: Waffle batter should be a similar consistency to pancakes, but the difference is waffles have more fat, whether it’s melted butter or oil.
Baking Powder: Baking powder gives the waffle a better rise than baking soda, but you can use baking soda in a pinch.
Don’t Overmix: It is ok for the batter for these bacon waffles to be lumpy. It is better to have some lumps than overmix.
Sacrifice First Waffle: The first waffle should be used to figure out how much batter you need and the level of doneness you want.
Don’t Peek: Let the waffle iron do its work and don’t continue to open it. Rely on the indicator if it has one and if it doesn’t, look for steam coming out of the side which indicates that it is done.
Use the Oven: To keep the bacon waffles from getting cold while cooking the others, place in a 200°F oven. Just place directly on the oven rack.