You might think all flours are created equally, but you're wrong. Probably the most popular flours of the bunch are cake flour and all purpose. These flours may look the same because they're both made from wheat. But according to The Kitchn, the difference lies in how they are milled, what wheat was used to produce the flour, and what time of the year it was harvested. But most importantly, protein content.
All Purpose flour has a protein content of 10-12% compared to Cake Flour's 7-8%. The lighter protein content creates a lighter consistency, which is why cake flour is typically used in cakes to create that airy texture. Both of these flours can be used interchangeably, for the most part. So when it comes to using cake vs all purpose flour, there might not be as big of a difference as you think.
Breads: All Purpose
The best type of flour to use for breads is all purpose or bread flour because of its high protein content. All purpose flour is best for breads like a white sandwich bread, or if you are making banana or pumpkin bread. You don't want to use cake flour here because the bread won't rise due to the low protein content. But if it's all you have on hand, you can add two tablespoons of cornstarch for every cup of flour.
Cakes: Either
You can go either way for cakes. For a lighter and airier type sponge cake, use cake flour. But if you don't have cake flour, don't worry because all purpose will do just the same thing. All purpose is going to create a denser cake, so it's all about preference.
Muffins: Either
Typically most muffin recipes call for all purpose flour and will create a dense, go-to muffin recipe. But if you're looking for a sweeter muffin, use cake flour. Cake flour will give your muffins a fluffier, more cake-like density.
Cupcakes: Either
Since cupcakes have a lot of sugar, you can use cake or all purpose flour here. Like a simple layer cake, cake flour will create a light and airy cupcake. All purpose will create a denser cupcake.
Pancakes & Waffles: All Purpose
Homemade pancake and waffle recipes typically call for all purpose flour. The protein in all purpose flour is crucial for the form and structure of your pancakes or waffles. So if you want fluffy pancakes, make sure to use all purpose flour (and these other fun tips).
Pie Crust: All Purpose
The crust will either make or break your pie. So when you're looking to make the perfect pie crust, opt for all purpose flour. The higher protein content will be easier to work with, and it will be more tender. You don't want to use cake flour here since it has a low protein content and your dough will be hard to work with.
Cookies: All Purpose
Who doesn't love a perfectly baked chocolate chip cookie? The trick in making cookies is using all purpose flour. Since all purpose has more gluten, it will leave you with a chewy and more put together cookie. Cake and pastry flours are going to create a runnier cookie that won't stick together.
In the end, all purpose flour seems to have cake flour beat as the universal flour. Although cake flour isn't far behind. If you don't have the flour called for a recipe on hand, make sure you look at the recipe first before switching flours.