Heat olive oil in a large skillet over medium heat.
Add minced garlic and sauté for 1 minute until fragrant, stirring frequently to prevent burning.
Pour in the crushed tomatoes and stir to combine.
Add salt, black pepper, and red pepper flakes to the tomato sauce. Stir well.
Reduce heat to low and simmer the tomato sauce for 10 minutes, stirring occasionally.
While the sauce simmers, cook the cheese tortellini according to package instructions in a large pot of boiling salted water until al dente, about 3-5 minutes. Drain and set aside.
Stir the heavy cream into the tomato sauce and cook for an additional 2 minutes until the sauce is creamy and heated through.
Add the cooked tortellini to the skillet and gently stir to coat the pasta evenly with the creamy tomato sauce.
Remove the skillet from heat and stir in the grated Parmesan cheese and chopped fresh basil.
Serve immediately, garnished with extra Parmesan and basil if desired.