Nordic Winter Vegetable Soup

Name: Nordic Winter Vegetable Soup
Ingredients: 2 tablespoons extra-virgin olive oil; 1 large onion, thinly sliced; 2 leeks, white and tender green parts only, thinly sliced; 2 garlic cloves, minced; 1 cup pearled barley; 8 cups low-sodium vegetable broth; 4 cups water; 10 thyme sprigs; 2 bay leaves; 1 1/2 pounds celery root, peeled and cut into 1/2-inch cubes; 1 pound parsnips, peeled and cut into 1/2-inch pieces; Salt and freshly ground pepper; 1 pound baby spinach; 1 teaspoon freshly grated nutmeg