In a large pot, heat olive oil over medium heat. Add diced onion and sauté until translucent, about 5 minutes.
Add minced garlic, diced carrots, diced zucchini, and sliced mushrooms to the pot. Cook, stirring occasionally, until vegetables are tender, approximately 7 minutes.
Stir in dried oregano, dried basil, and red pepper flakes (if using). Cook for an additional minute until fragrant.
Pour in vegetable broth and crushed tomatoes. Bring the mixture to a boil.
Add broken lasagna noodles to the pot. Reduce heat to a simmer and cook until noodles are al dente, about 10 minutes, stirring occasionally to prevent sticking.
Stir in chopped fresh spinach and cook until wilted, about 2 minutes. Season the soup with salt and freshly ground black pepper to taste.
In a small bowl, combine ricotta cheese, shredded mozzarella, grated Parmesan, and chopped fresh basil.
To serve, ladle soup into bowls and top each with a generous spoonful of the cheese mixture. Garnish with additional fresh basil if desired.