In a large pot, heat the olive oil over medium heat. Add the diced onion and sauté for about 5 minutes until translucent.
Add the minced garlic and sauté for an additional minute until fragrant.
Pour in the crushed tomatoes and vegetable broth. Stir to combine.
Add the dried basil, dried oregano, and red pepper flakes (if using). Bring the mixture to a simmer and cook for about 10 minutes to allow the flavors to meld.
Add the cheese tortellini to the pot and cook according to package instructions, usually about 4-5 minutes until they float to the top.
Reduce the heat to low and stir in the heavy cream, allowing it to warm through for another 2-3 minutes.
Season with salt and black pepper to taste.
Ladle the soup into bowls, garnish with fresh basil leaves, and top with grated Parmesan cheese.