In a medium bowl, whisk together the eggs, sour cream, and buttermilk.
In a large bowl, whisk together the flour, sugar, baking powder, baking soda, and salt.
Pour the wet ingredients into the flour mixture and mix until barely combined.
Stir in the club soda and melted butter. Don’t mix it until smooth, the batter should be lumpy.
Let the batter sit for 10 minutes. Meanwhile, heat the waffle iron.
Drop the appropriate amount of batter into the hot waffle iron. (I used ¼ cup of batter for a 4-inch waffle maker.) Cook the waffles until golden brown, about 5 minutes.
Transfer the cooked waffles onto a wire rack and repeat with the remaining batter.
Notes
Note 1: Buttermilk substitute: Mix 1 ½ cups sour cream with ½ cup of water.Note 2: You may use unflavored sparkling water in place of club soda. Tonic water made the waffles slightly bitter note.Storing Tips: - Let the waffles cool to room temperature, then store in an airtight container in the refrigerator for up to 6 days, or in the freezer for up to 3 months. - I recommend storing the waffles in the freezer so they don't dry out, then reheating in a toaster or toaster oven until hot and crispy. - Never reheat waffles in the microwave, lest you ruin their beloved texture. They will lose their crisp edges and get soft/chewy.