Heat olive oil in a large skillet over medium heat.
Add minced garlic and sauté for 1 minute until fragrant, stirring constantly to avoid burning.
Pour in the crushed tomatoes and stir to combine with the garlic.
Simmer the tomato sauce for 10 minutes, stirring occasionally.
Stir in the heavy cream, grated Parmesan cheese, salt, black pepper, and red pepper flakes.
Continue to cook the sauce for 3-4 minutes until it thickens slightly.
Meanwhile, cook the cheese tortellini according to package instructions until al dente, then drain.
Add the cooked tortellini to the skillet with the creamy tomato sauce and gently toss to coat evenly.
Remove from heat and stir in the chopped fresh basil leaves.
Serve immediately, garnished with additional Parmesan cheese if desired.