In a large pot, heat the olive oil over medium heat. Add the diced onion and sauté for 5-7 minutes until it becomes translucent.
Stir in the minced garlic and cook for an additional 1-2 minutes until fragrant.
Pour in the crushed tomatoes, vegetable broth, oregano, basil, and red pepper flakes (if using). Bring the mixture to a simmer and let cook for 10 minutes.
Add the refrigerated tortellini to the pot and cook according to package instructions, usually about 4-5 minutes.
Lower the heat, then stir in the heavy cream. Allow the soup to warm through, about 2-3 minutes.
Season with salt and pepper to taste, adjusting for your preference.
Serve hot, garnished with fresh basil leaves and a sprinkle of grated Parmesan cheese.
Notes
Serve the soup in wide bowls for a comforting feel and sprinkle extra Parmesan on top. Enjoy with crusty bread on the side!