1. Begin by heating a large pot over medium heat and add 1 tablespoon of olive oil. Sauté ground chicken or Italian sausage until browned and fully cooked, breaking it into small pieces. Once done, remove it from the pot and set it aside.
2. Using the same pot, add more oil if needed. Add chopped onion and cook until soft and translucent, about 3-4 minutes. Stir in minced garlic and cook for an additional minute. For extra flavor, add sliced mushrooms if desired and cook until tender.
3. Gently stir in baby spinach and allow it to wilt for 1-2 minutes, incorporating it well with the onions and garlic.
4. Pour in chicken broth (6 cups) followed by marinara sauce (1 cup). Stir everything together and bring the mixture to a gentle simmer.
5. Break lasagna noodles into small pieces (about 2 inches each) and add them to the pot. Cook until the noodles are tender, about 10-12 minutes, stirring occasionally to prevent them from sticking to the pot.
6. While the noodles are cooking, prepare the Alfredo sauce in a separate saucepan. Melt butter (2 tablespoons) over medium heat, then whisk in flour (2 tablespoons) to form a roux. Gradually whisk in heavy cream (1 cup) while stirring to avoid lumps. Once thickened, fold in grated Parmesan cheese (½ cup) and stir until smooth.
7. Carefully pour the prepared Alfredo sauce into the pot with the soup. Stir well to ensure the sauce is evenly distributed. Allow the soup to simmer for an additional 5 minutes, letting all the flavors meld together.
8. If desired, sprinkle shredded mozzarella cheese into the soup for a gooey, cheesy finish.
9. Serve the soup in bowls, garnishing with freshly grated Parmesan and a pinch of Italian seasoning. Enjoy warm, paired with crusty bread or a side salad for a complete meal.