Brown the Meat: In a large soup pot or Dutch oven, heat the olive oil over medium heat. Add the ground beef or turkey, breaking it apart with a spoon, and cook until browned. Drain any excess fat if needed.
Sauté Aromatics: Add the chopped onion and cook until softened, about 5 minutes. Stir in the garlic and cook for an additional minute until fragrant.
Add Tomato Base and Seasonings: Pour in the diced tomatoes, tomato sauce, and chicken broth. Add the Italian seasoning, red pepper flakes (if using), and salt and pepper. Bring to a simmer.
Cook the Pasta: Add the broken lasagna noodles (or short pasta) to the pot and cook for 10-12 minutes, or until the pasta is al dente. Stir occasionally to prevent sticking.
Finish with Cheese: Just before serving, stir in the ricotta, mozzarella, and Parmesan cheese, allowing it to melt into the soup. Adjust seasoning to taste.