In a large bowl, whisk together the flour, sugar, baking powder and salt.
Place the egg yolks into a small bowl. Then whisk in the milk, oil and vanilla. Then stir into the flour mixture.
Beat the egg whites until stiff peaks form, about 2 minutes. Then fold into the batter. Do not over mix.
Preheat your waffle iron on medium-heat, then spray with non-stick spray. Add about 1/2 cup of the batter to the grid and cook until the waffle iron goes off, about 3 minutes.
Notes
To add a special touch, you can mix in 1/4-1/2 cup Belgian pearl sugar.
To keep warm: Place on a baking sheet in the oven at 175°F to keep warm.To store: Store leftovers in a zip top bag and place in fridge for 2-3 days.Freezing: Let cool, then place in a freezer bag. Store in freezer for up to 3 months.To reheat: Reheat in the microwave or toaster oven for 30 seconds, or until warm throughout. You can also place in the oven at 250°F for 5-10 minutes or until warm and crispy.