In a large pot over medium heat, heat the olive oil. Add the onion and garlic and cook, stirring occasionally, until the onion is softened, about 5 minutes.
Add the carrots, celery, oregano, basil, red pepper flakes, salt, and black pepper and cook, stirring occasionally, for 5 minutes.
Add the vegetable broth and diced tomatoes and bring to a boil. Reduce the heat to low and add the frozen tortellini. Simmer for 15 minutes, stirring occasionally.
Remove from the heat and stir in the Parmesan cheese and parsley.
Interesting Facts
Tortellini is a type of Italian pasta that is usually filled with cheese or meat.
This soup can be made with any type of broth or stock.
You can use fresh or frozen tortellini in this recipe.