Step 1: Sauté the Aromatics : In a large soup pot or Dutch oven, heat olive oil over medium heat. Add diced onion, carrots, and celery. Sauté for 6–8 minutes until softened and fragrant. Stir in minced garlic and cook for another 30 seconds.
Step 2: Add Vegetables and Tomato Base : Add zucchini and cook for 2–3 minutes. Stir in tomato paste, coating the vegetables evenly. Add the chopped tomatoes, herbs (oregano, basil, thyme), and bay leaf. Stir well to combine.
Step 3: Add Broth and Beans : Pour in the vegetable broth and water (if needed). Add the white beans and season with salt, pepper, and crushed red pepper flakes. Bring to a boil, then reduce the heat to low and simmer for 20–25 minutes until the vegetables are tender and the flavors meld together.
Step 4: Add the Kale : Stir in the chopped kale and simmer for another 5–8 minutes until the greens are wilted but still vibrant. Adjust seasoning — taste and add more salt, pepper, or herbs as needed.
Step 5: Optional Enrichment : For extra heartiness, stir in cooked small pasta or diced potatoes at this stage. For a touch of richness, stir in a drizzle of olive oil or a spoonful of Parmesan cheese before serving.