Top the onion, cut in half, and peel. Finely dice.
Heat the olive oil in a large saucepan. Add the onion, and cook until soft, about 10 minutes.
Add the quinoa and salt, and stir until every grain is coated in oil.
Add enough water to the pan so that the quinoa is covered by 1cm of water: you should have equal volumes of water to quinoa.
Bring up to a vigorous boil, cover with a lid, and turn down the heat so that the quinoa simmers gently. Leave to cook for 15 minutes.
Adjust the seasoning, and serve.
«Quinoa is a great source of protein, and is therefore more filling than other grains. »