Great question! Usually people wonder about substituting matzo meal for cake meal, but I haven't heard the question in reverse until now. The answer may depend a bit on what you're making, but I wouldn't advise doubling the cake meal. Why? Both matzoh meal and cake meal are simply ground up matzoh; cake meal is just ground to a finer, powder-like consistency.
If you wanted to make your own cake meal, you could grind matzoh meal in a blender or food processor, but you'd only need about 1 cup plus 2 tablespoons of matzoh meal to yield 1 cup of cake meal. So if, for example, your recipe calls for 3/4 cup of matzo meal, you could try 3/4 cup plus 4.5 teaspoons of cake meal.
While matzo cake meal generally works well in cake and cookie recipes, keep in mind that if you're making something like matzo balls, kugel, or Pesach rolls, they may turn out denser or clumpier if you substitute cake meal for matzoh meal. In cases like that, it's a good idea to stick to the original recipe.More Tips for Passover Cooking Success:
Wondering what to use in place of graham cracker crumbs or corn syrup on Passover? Did you run out of matzo farfel, but wish you could make another batch of Matzo Farfel Cookies? Check out Passover Cooking Substitutions for ingredient swaps and tips to help you tweak favorite recipes for Pesach use.