Quinoa cooks quickly—in about 15 minutes or less. Some package directions tell you to turn off the heat once the liquid boils and you’ve stirred in the quinoa. We prefer to bring the cooking liquid to a boil, stir in the quinoa, then turn down the heat to low, cover and simmer gently, until all of the liquid is absorbed, about 15 minutes. You will know when the quinoa is done because it will look like it has popped open—revealing the germ of the kernel.