In a large pot or Dutch oven, heat the olive oil over medium heat.
Add the onion, zucchini, and red bell peppers, and let them sauté for about 5-7 minutes, stirring every few minutes.
Add in the marinara, tomatoes, spices, and broth, and bring the soup to a simmer. Once simmering, throw in the spinach and the noodles. Bring the heat down to low and let the soup simmer for about 15 minutes, or until the noodles are cooked. Give the soup a stir every once in a while to keep the noodles from sticking together.
As the soup simmers, make the cheese mixture by placing the ricotta, mozzarella, and parmesan into a small blender or food processor. Add a tablespoon of milk and blend. Check the consistency, and keep adding milk by the tablespoon until you have yourself a smooth texture.
Once the noodles are fully cooked, the soup is ready to serve. Ladle servings into bowls and top each with a generous dollop of the cheese mixture.
Garnish with fresh basil and a pinch or two of chili flakes for an extra kick.