Winter Vegetables and Bulgur

Name: Winter Vegetables and Bulgur
Yield: 4 main-course
Ingredients: 2 tablespoons olive oil; 4 cups 3/4-inch pieces chopped peeled assorted root vegetables (such as carrots, turnips, celery root, and golden beets); 2 cups chopped onions; 4 cups vegetable broth; 1 rounded teaspoon herbes de Provence; 1 1/2 cups bulgur (about 8 ounces); 1 6-ounce package baby spinach leaves