Heat olive oil in a large pot over medium heat.
Add the onion and sauté until translucent, about 5 minutes.
Stir in the minced garlic and cook for 1 more minute.
Pour in the crushed tomatoes and broth, and stir to combine.
Add dried oregano, dried basil, salt, and pepper; stir well.
Bring the mixture to a gentle simmer and cook for about 10 minutes.
Add the cheese tortellini and cook according to package instructions, usually around 5-7 minutes.
Taste and adjust seasoning if necessary before serving.
Serve hot, garnished with fresh basil leaves.