If a recipe asks for cake flour specifically, it is better not to substitute with any other flour but general substitution formula for 1 cup of cake flour is equivalent to 1 cup of all purpose flour minus two tablespoons. Some also say you can add about 2 tablespoons of cornstarch to the all purpose flour.
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If a recipe asks for cake flour specifically, it is better not to substitute with any other flour but general substitution formula for 1 cup of cake flour is equivalent to 1 cup of all purpose flour minus two tablespoons. Some also say you can add about 2 tablespoons of cornstarch to the all purpose flour.