Can quinoa be used instead of flour for cookies?
I have used quinoa flour in various recipe and it would have a similar effect as the brown rice flour, though its taste would differ. I would recommend against substituting it (at least not 1:1) for the tapioca flour as that is likely working as a kind of binding agent to some extent. Experimentation may yield different results based on the ratio, but also tapioca has less flavor (which may be ideal as a balance).