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 combination of baking soda and an acid, typically cream of tartar. When combined, they produce carbon dioxide gas that helps lighten the texture. In cream sauces, this reaction can help maintain a smooth, slightly aerated texture without making the sauce dense or heavy.
To ensure even leavening, mix the baking soda and cream of tartar thoroughly before incorporating into the sauce. Avoid adding too much liquid afterward to prevent thinning the sauce excessively.
Compared to commercial baking powder, this substitute offers a fresher, more controlled reaction and avoids potential additives, preserving the cream sauce's intended flavor and texture.