Hearty Minestrone Soup

In a pot, cover beans with 2 inches water and bring to a boil. Simmer over low heat until tender, about 2 hours; add water to keep beans covered. Drain beans and reserve cooking liquid. Meanwhile, in another pot, heat 2 tablespoons oil. Add pancetta and cook over moderate heat until crisp, 4 minutes. Add shallots, celery, onion, carrot, and fennel, and cook until softened. Add garlic, crushed pepper, and bay leaves and cook, stirring, until fragrant. Add tomato paste and cook, stirring, 2 minutes. Stir in tomatoes and broth; bring to a boil. Simmer over low heat 1 hour. Add beans and enough cooking liquid to thin out soup. Discard bay leaves; season with salt and pepper. In a bowl, toss arugula and parsley with lemon juice and remaining 1 tablespoon oil. Season with salt and pepper. Serve soup in bowls; top with salad.