Sauté the vegetables: Heat olive oil in a large saucepan over medium heat. Add the carrot, celery, onion, garlic, and chili flakes, cooking for about 5-8 minutes until softened and lightly golden.
Infuse with rosemary: Add the sprig of rosemary and cook for another 3-4 minutes, stirring occasionally to release its aroma. Reduce the heat to low, remove the rosemary, and mix in the tomato purée until combined.
Simmer the beans and broth: Stir in the borlotti beans and allow them to absorb the flavors. Gradually pour in the vegetable stock, add the bay leaf, and season with salt. Bring the mixture to a boil.
Cook the pasta: Stir in the pasta, cover, and cook until it reaches an al dente texture.
Mash for creaminess (optional): Take the pan off the heat and mash some of the beans with a fork to give the soup a richer, creamier consistency.
Final touches: Discard the bay leaf and stir in nutritional yeast and spinach. Season with salt and pepper, mixing until the spinach has completely wilted. If the soup is too thick, add a splash of hot water or vegetable stock.
Serve and enjoy: Ladle into bowls and top with plant-based Parmesan-style cheese, chili oil (if using), croutons, and extra chili flakes for added heat.