Spring Onion Noodle Soup with Lemon Sour Cream and Herbed Cheese Toast

Name: Spring Onion Noodle Soup with Lemon Sour Cream and Herbed Cheese Toast
Ingredients: 1/4 cup butter; 1 tablespoon olive oil; 1 large sweet onion, thinly sliced (Vidalia is perfect for this); 1-3 large leeks, white part only, thinly sliced; 1 bunch green onions, thinly sliced; 2 cups fresh or frozen shelled peas; 4 cups reduced-sodium chicken broth; 4 cups water; 8 ounce small pasta (like alphabet or ditalini); 1 cup loosely packed, torn basil leaves (Chiffonade); zest and juice of 1 lemon; salt to taste; Lemon Sour Cream, optional (below); 1/2 cup sour cream; 1/4 cup mayonnaise; 1/4 cup chopped chives; 1 tablespoon lemon juice; dash of garlic powder; salt and pepper to taste; French baguette (or similar); 2 tablespoons dried oregano; 2 tablespoons dried basil; 1 tablespoon onion powder; 1 tablespoon garlic powder; 1/4 cup shredded Parmesan; 1/4 cup shredded mozzarella; salt and pepper