Cassava flour is made from the root of the cassava plant and is widely used in cooking in South Asia. However, this fine flour is gaining in popularity in the UK as a much closer alternative to wheat for people either allergic to or intolerant of the gluten in ordinary flour.
Unlike many gluten-free flours, cassava flour appears to mimic ordinary flour perfectly, and can be directly substituted in recipes. As a bonus, it is also a good source of vitamin C, plus the minerals copper and folate. You’ll find it in larger supermarkets and whole food stores.