Is it ok to substitute all purpose flour for cake flour?

It's not ideal, but you can sometimes substitute all-purpose flour for cake flour, but it won't be the same as using the real thing.

Here's why and how to make it work better:

Why it's not ideal:

* Protein content: Cake flour has a lower protein content (around 7-8%) compared to all-purpose flour (around 10-12%). This lower protein content means the gluten development in cake flour is less, resulting in a softer, more delicate texture.

* Starch: Cake flour also contains a higher percentage of starch, contributing to its fine crumb and light texture.

How to make the substitution work better:

1. Reduce the amount of all-purpose flour: Use 1 cup of all-purpose flour for every 1 1/4 cups of cake flour called for in the recipe.

2. Add cornstarch: For every 1 cup of all-purpose flour, add 2 tablespoons of cornstarch. This will help mimic the lower protein content and higher starch content of cake flour.

3. Don't overmix: Overmixing will develop gluten, leading to a tough cake. Mix just until the ingredients are combined.

Keep in mind:

* This substitution won't perfectly replicate the results of using cake flour, but it can get you closer to the desired texture.

* If you're making a recipe that relies heavily on the delicate texture of cake flour, it's best to use it if possible.

* If you're a beginner baker, it's recommended to use cake flour for cakes unless you're confident in your skills and willing to experiment.

Overall, while substituting is possible, it's not recommended unless you have no other choice. If you're serious about baking, investing in cake flour is a worthwhile investment.