Combine flour, yeast, cinnamon, ginger, nutmeg, sugar, and salt in a large mixing bowl. Measure out 1 ½ cups of milk. Add to that the pumpkin puree, melted butter, and egg yolks and mix to combine.
In a separate bowl, place the egg whites. Beat with a mixer until the whites form stiff peaks.
Add the liquid mixture to the dry mixture. Mix together until the ingredients are just combined. Do not over mix.
Gently fold in the whipped egg whites.
Cover and place in the fridge for 8 hours or overnight.
Set your waffle iron to it's highest setting. Rub the waffle iron with butter (before each waffle).
Ladle in about ⅓ cup of the batter and cook for about 2 to 4 minutes or until golden brown. Should make about 8 waffles depending on the size of your waffle iron,