How To Make Classic Minestrone Soup

Name: How To Make Classic Minestrone Soup
Prep time: 15 min
Cook time: 1 h
Total time: 1 h 15 min
Cuisine: Italian, European
Ingredients: 1 medium yellow onion; 6 medium stalks celery; 1 large zucchini; 3 medium carrots; 1 small sweet potato; 2 cloves garlic; 1 (15-ounce) can white beans, such as cannellini or Great Northern; 2 tablespoons olive oil; 2 tablespoons unsalted butter; 2 teaspoons kosher salt, plus more for seasoning; 1 (2x3-inch) Parmesan rind; 1 (28-ounce) can diced tomatoes; 6 cups low-sodium vegetable or chicken broth; 1/2 medium lemon; 2 tablespoons basil pesto, plus more for serving; 4 cups baby spinach or baby kale; Parmesan cheese and crusty bread, for serving