Over a medium flame, heat the olive oil in a large pot. Add the onion and sauté until translucent, about 10 minutes. Add the celery, parsnips, and carrots and sauté for 10 to 15 minutes, or until vegetables start to soften. Add the mushrooms and raise the flame to medium-high (the mushrooms will release a lot of liquid and you want it to cook out) and cook for about 15 to 20 minutes more. Stir occasionally, but not too often because you want the vegetables to have some golden color.

Add water and scrape up any bits from the bottom. Cover pot and raise flame to bring to a boil. Once boiling, add barley and then reduce to a simmer. Cook for about 45 minutes, until all ingredients are fully cooked and tender. Add spices, adjusting to taste if necessary.