Cut the chicken into bite-sized pieces and season with salt and black pepper.
Heat the olive oil in a large nonstick skillet over medium-high heat. Add the chicken and cook about 2 minutes, turning as needed, until browned on the outside.
Add the minced garlic to the skillet and cook 1 minute, stirring, until fragrant.
Pour in the half-and-half, then stir in the basil pesto and crushed red pepper flakes until combined and the sauce begins to simmer.
Add the refrigerated tortellini, pressing them into the liquid so they are as submerged as possible. Reduce heat to maintain a gentle simmer (do not boil).
Cover the skillet with a lid and cook 4 to 5 minutes, or until the tortellini are heated through and tender.
Remove the skillet from the heat and stir in the slivered sun-dried tomatoes and shredded Parmesan until the cheese melts into the sauce.
Taste and adjust seasoning with salt and black pepper if needed. Sprinkle with chopped parsley and serve immediately.
