Preheat Belgian waffle maker.
In a medium bowl, whisk together flour, baking powder, salt and spices until evenly incorporated.
In a small bowl or 2-cup glass measuring cup, whisk together egg yolks and buttermilk. Add to dry ingredients and stir with a rubber spatula just until no streaks of dry ingredients remain (the mixture may still be a little lumpy, that's ok). Mix in melted butter.
Beat egg whites with an electric mixer or in the bowl of a stand mixer fitted with a whisk attachment. Beat on medium-high speed until the whites hold medium-soft peaks.
Fold in ⅓ of egg whites into batter to lighten; add remaining egg whites and fold until almost incorporated. Fold in the shredded cheese.
Scoop a scant cup of batter (I use a large cookie scoop, and 3 heaping scoops is just about perfect) into preheated waffle maker. You may need more or less batter depending on your specific machine, refer to manufacturer's instructions. Cook for about 5 minutes (longer than you would for a typical sweet waffle) or until waffles are deep golden brown and crisp. Remove from waffle maker and serve warm.
Leftover waffles can be cooled on a wire rack, then refrigerated in an airtight bag for up to 3 days or frozen for up to 3 months. Rewarm the waffles in a 300-degree oven for about 10 minutes or until heated through and crispy.
