Baking Soda and Cream of Tartar (Best Option)
1/4 teaspoon baking soda + 1/2 teaspoon cream of tartar per 1 teaspoon baking powderBaking powder is essentially a mixture of baking soda (a base) and an acid, often cream of tartar, which react to produce carbon dioxide gas for leavening. Combining baking soda with cream of tartar mimics this reaction, providing the necessary lift in waffle batter.
To ensure success, mix the two powders thoroughly before adding to the batter to avoid uneven leavening. Use immediately after mixing to maximize the reaction since it begins as soon as wet ingredients are combined.
Compared to commercial baking powder, this substitute delivers comparable rise and texture, though the flavor may be slightly more acidic if not balanced well with other ingredients.