Preheat oven to 210 degrees C. Line two baking sheets with parchment paper.
In a shallow dish combine quinoa flour, arrowroot powder, paprika, cayenne and salt. Whisk together buttermilk and eggs in a in a separate shallow dish.
Place quinoa and quinoa flakes in a blender and pulse until crumbly. Place in a shallow dish.
Dredge onion rings into the flour mixture, then dip into the buttermilk mixture. Drain excess batter and dredge into the quinoa mixture.
Arrange on the prepared baking sheets in a single layer. Spray well with olive oil. Cook until golden brown, about 20-25 minutes, flipping the onion rings over about half way through and re-spraying. Serve with dipping sauce.