Baking Soda and Cream of Tartar (Best Option)
1/4 teaspoon baking soda + 1/2 teaspoon cream of tartar per 1 teaspoon baking powderThis combination mimics the chemical leavening of baking powder by combining an acid (cream of tartar) and a base (baking soda), producing carbon dioxide gas to aerate the batter. In pound cake, which relies on a delicate balance of fat and flour, this ensures the batter rises evenly without altering flavor.
To succeed, mix the baking soda and cream of tartar thoroughly with the dry ingredients to ensure even distribution. Avoid adding extra acidic ingredients to prevent over-leavening.
The final cake will have a similar dense yet tender crumb and buttery flavor as with commercial baking powder, preserving the traditional pound cake characteristics.