Melt butter in a saucepan over medium heat. Add the quinoa and stir-fry until lightly browned, about 5 minutes. Add stock and bring to the boil. Reduce to a simmer, cover, and cook for 15 minutes, or until quinoa is tender.
In a bowl, mix quinoa together with garlic, parsley, thyme, salt and onion. Sprinkle with lemon juice, and serve.