Bring a large pot of salted water to a boil. Cook pasta until al dente. Reserve ½ cup pasta water, then drain.
Season sliced chicken with salt and black pepper.
Heat olive oil in a large skillet over medium heat. Cook chicken for 4–5 minutes until golden and cooked through. Remove and set aside.
In the same skillet, melt butter and add garlic. Cook for 30 seconds until fragrant.
Stir in sun-dried tomatoes and cook for 1–2 minutes.
Pour in chicken broth and heavy cream. Bring to a gentle simmer.
Reduce heat to low and stir in parmesan cheese, Italian seasoning, and red pepper flakes if using.
Add cooked pasta and chicken back to the skillet. Toss gently, adding reserved pasta water as needed to loosen the sauce.
Garnish with fresh herbs if desired and serve hot.
