Hearty Vegetable Soup | America's Test Kitchen

Ingredients

• 1 large carrot , peeled and chopped medium
• 1 rib celery , chopped medium
• 1 medium onion , chopped medium
• 3 medium portobello mushrooms , roughly chopped
• 1 medium head garlic , outer papery skins removed and top third of head cut off and discarded
• 3 tablespoons olive oil
• 1 tablespoon tomato paste (heaping)
• 9 cups low-sodium chicken broth or vegetable broth
• 2 medium leeks (about 1 pound), green parts chopped, white parts sliced thin crosswise
• 10 sprigs fresh parsley leaves
• 4 sprigs fresh thyme
• 2 bay leaves
• 1/2 ounce dried porcini mushrooms , rinsed
• 1 (14.5-ounce) can diced tomatoes , drained, tomato pieces chopped coarse
• 2 small russet potatoes (about 12 ounces), peeled and cut into 1/2-inch cubes (about 1 1/2 cups)
• 2 medium carrots , peeled and cut into 1/2-inch cubes (about 1 cup)
• 1/2 medium celeriac (about 12 ounces), peeled and cut into 1/2-inch cubes (about 1 1/2 cups)
• 1 small head escarole (about 12 ounces), washed, stemmed, and leaves cut into 1-inch pieces (about 4 heaping cups)
• 1 cup frozen baby lima beans (6 ounces) defrosted (optional)
• 2 tablespoons minced fresh parsley leaves
• Salt and ground black pepper