Heat a large heavy-bottomed pot over medium heat. Add 3 tbs extra-virgin olive oil. When shimmering, add the diced onion, carrots and celery. Season lightly with 1/4 tsp of the salt. Cook, stirring occasionally, until the vegetables are softened and the onion is translucent, about 6–8 minutes.

Add garlic and summer veg

Stir in the minced garlic and cook 30–45 seconds until fragrant. Add the zucchini and the seasonal vegetables (e.g., diced butternut squash or green beans). Cook 3–4 minutes, stirring, until they begin to soften.

Tomato base

Push the vegetables to the side and add the tomato paste. Cook for 1 minute, stirring, to deepen the flavor. Mix the tomato paste into the vegetables. Add the canned crushed tomatoes and stir to combine.

Simmer

Pour in 6 cups vegetable broth and 1 cup water. Add dried oregano, dried thyme, bay leaf, remaining salt (about 1 1/4 tsp) and pepper and red pepper flakes if using. Bring to a gentle boil, then reduce heat and simmer, partially covered, for 12–15 minutes to marry flavors and finish cooking the seasonal vegetables.

Legumes & Pasta

Add beans and pasta

Stir in the rinsed cannellini beans. Increase heat to bring the soup to a simmer and add the ditalini. Cook uncovered, stirring occasionally, until the pasta is al dente, following package timing (about 8–10 minutes). If the soup becomes too thick, add up to 1/2 cup more water or broth to reach desired consistency.

Greens

When the pasta is nearly cooked, stir in the spinach or chopped kale. Cook 1–2 minutes until wilted. Taste and adjust seasoning with additional salt and pepper as needed.

Finishing & Garnish

Brighten and finish

Remove the bay leaf. Stir in 1 tbs fresh lemon juice and 2 tbs chopped parsley. Off the heat, stir in 1/2 cup grated Parmigiano-Reggiano so it melts into the soup, adding body and savory depth. If desired, reserve the shaved Parmigiano for plating.

Serve: Ladle the soup into bowls, sprinkle with reserved shaved Parmigiano and an extra pinch of parsley.

Grilled Bread

Prepare bread

Preheat a grill pan or outdoor grill to medium-high (or preheat broiler). Brush both sides of each bread slice lightly with 2 tbs olive oil and sprinkle the cut sides with 1/4 tsp salt.

Grill

Grill the bread slices until golden and slightly charred, about 1–2 minutes per side on a hot grill pan (or 1–3 minutes under a broiler, watching carefully).

Garlic finish

Optionally rub the hot grilled bread with the halved garlic clove so a hint of garlic transfers to the bread. Serve alongside the bowls of minestrone for dipping or topped with shaved Parmigiano.