Serves 6.
1 Tbsp canola oil
2 large onions, diced
1 large garlic clove, minced
1/4 lb fresh cremini or button mushrooms, sliced
8 cups vegetable stock (or chicken stock)
1 large carrot, thinly sliced
2 large celery stalks, thinly sliced
3 Tbsp tomato paste
1/2 cup rutabaga or turnip, peeled and diced
1/4 cup pearl barley
1/4 cup fresh parsley leaves, roughly chopped
2 large bay leaves
1 tsp dried marjoram leaves
1/2 tsp dried thyme leaf
1/2 tsp powdered mustard
1/4 tsp celery seed
Dash of cayenne pepper (or to taste)
1/4 tsp black pepper, or to taste
1/2 cup grated Parmigiano-Reggiano cheese (optional)
In a 5-quart Dutch oven or small stock pot, combine the oil, onions, garlic and mushrooms, plus 2 tablespoons of the stock. Cook over medium heat, stirring frequently, until the onion is tender, 4-5 minutes. If the vegetables begin to stick to the pot, add a few more tablespoons of stock.
Add all remaining ingredients to the pot, stir well to incorporate the tomato paste, and bring to the boil. Cover, lower the heat to simmer, and cook for 1-1/2 hours or until the barley is tender and the soup is lightly thickened.
With a large spoon, skim any oil off the surface of the soup and discard. If you wish, top with grated Parmigiano-Reggiano cheese.