Start by gathering all your ingredients. Mince the garlic, zest the lemon, toast the pine nuts, and chop the basil. Slice the grilled chicken breasts thinly. This mise en place will make the cooking process smooth and efficient.

Bring a large pot of salted water to a boil. Add the linguine or fettuccine and cook according to the package instructions until al dente. Drain the pasta and set it aside.

In a large skillet, heat the extra-virgin olive oil over medium heat. Add the minced garlic and sauté until fragrant, about 1-2 minutes. Make sure not to burn the garlic, as it can become bitter.

Stir in the lemon zest, toasted pine nuts, sun-dried tomatoes, and fresh basil. Cook for another 2 minutes. Pour in the heavy cream and chicken broth, stirring to combine. Let the mixture simmer until it thickens slightly, around 5-7 minutes.

Gradually add the freshly grated Parmesan cheese into the sauce, stirring continuously until melted and well incorporated. Season with salt, freshly ground black pepper, and crushed red pepper flakes to taste.

Add the cooked pasta to the skillet, gently tossing to coat the pasta in the creamy sauce. If the sauce is too thick, add a splash of pasta water to loosen it up. Finally, fold in the thinly sliced grilled chicken.