Cook rinsed quinoa in broth according to package directions.

While the quinoa is cooking, in a large heavy sauté pan add olive oil to the pan, then the onion, sauté one minute.

Add the fennel, celery, and carrots, salt and pepper to taste; cook about 12-15 minutes over medium heat, until vegetables are soft.

Add the mushrooms to the pan, more salt and pepper if needed, cook, stirring 5 minutes, then cook covered for 2 minutes, or until mushrooms release their juice and are cooked through.

Add the cooked quinoa to the pan and mix well.