When wheat flour isn't an option in baking, whether that is due to a gluten allergy or a low-carbohydrate lifestyle, coconut flour is a viable alternative to a certain degree--plus, it's high in fiber. Coconut flour cannot be substituted cup for cup with wheat flour, as the resulting texture of the baked good is far too dense. Store-bought coconut flours, such as from Bob's Red Mill, can be more expensive than wheat flour. So instead of purchasing it, make your own coconut flour from coconut flakes while also making a byproduct of fresh coconut milk.
Soak 1 cup unsweetened coconut flakes in 4 cups water for several hours.
Transfer the coconut and water mixture to a food processor and process until smooth.
Strain the mixture through a cheesecloth; squeeze to get out the most liquid. This liquid is your coconut milk. Transfer the liquid to a container and refrigerate.
Spread the pulp from the cheesecloth onto a baking sheet.
In a 200-degree oven, bake the pulp until dry.
Grind the dried pulp until you have a fine powder texture.