Cook the frozen tortellini according to the package instructions until al dente. Drain and set aside.
Season the chicken breasts with salt and black pepper.
In a large skillet, heat olive oil over medium-high heat. Add the chicken breasts and cook until golden brown and cooked through, about 6-7 minutes per side. Remove the chicken from the skillet and set aside.
In the same skillet, add minced garlic and sauté for about a minute until fragrant. Pour in the chicken broth, scraping up any browned bits from the bottom of the skillet. Allow the broth to simmer for 2-3 minutes, reducing slightly.
Lower the heat and add the heavy cream, grated Parmesan cheese, sun-dried tomatoes, dried basil, dried oregano, and red pepper flakes (if using). Stir continuously until the cheese is melted, and the sauce is smooth and creamy.
Add the cooked tortellini and chicken to the skillet with the creamy sauce. Gently toss to coat the tortellini and chicken evenly with the sauce. Cook for an additional minute or two until everything is heated through.
Divide the creamy chicken and tortellini among plates. Garnish with additional grated Parmesan and black pepper.