How to make cake flour out of ordinary flour ?
Plain or all purpose flour types could be quite easily transformed to create a cake flour type like properties, in baking behaviour. Because the weight of cake flour is much lower due to its density, a portion of the standard flour being converted can be substituted with potato flour or cornstarch (called also maize or cornflour) instead. This tactic lowers down its protein and gluten percentage (hence the lower density) which therefore gives the body properties similar to those of the cake flour. For the ratio: simply remove 3 tablespoons out from the flour that is being converted and replace them with also 3 tbsp. of either the potato flour or the cornstarch.
