Bring a large pot of salted water to a boil, then add rigatoni and cook until al dente according to package instructions. Visual cue: the pasta should be tender but still firm in the center.

Reserve 1/2 cup of pasta water, then drain the rigatoni and set aside. Visual cue: a small glass amount of starchy water remains for loosening the sauce later.

Pat the chicken breasts dry, then season both sides with salt, black pepper, garlic powder, and Italian seasoning. Visual cue: the surface looks evenly coated with seasoning.

Heat olive oil in a large skillet over medium-high heat and sear chicken breasts for 5–6 minutes per side until deeply golden and cooked through (internal temp 165°F). Visual cue: browned edges and a thermometer reading of 165°F in the thickest part.

Remove the chicken to a cutting board and let it rest for 10 minutes. Visual cue: juices settle and the chicken remains juicy when sliced.

In the same skillet over medium heat, add minced garlic and red pepper flakes and sauté for 30 seconds until fragrant, without letting it burn. Visual cue: the garlic smells aromatic and turns lightly golden at the edges.

Stir in the sun-dried tomatoes and cook for 1 minute to warm and release their oil into the pan. Visual cue: the sauce base becomes tinted and glossy from the tomato oil.

Pour in chicken broth and scrape up the golden bits from the bottom of the pan, then let it reduce for 2 minutes. Visual cue: you see small caramelized flecks dissolve into the liquid.

Reduce heat to medium-low, pour in heavy cream, and stir to combine. Visual cue: the mixture turns creamy and begins to steam gently.

Simmer gently for 4–5 minutes until the sauce thickens. Visual cue: the sauce coats a spoon and leaves a slow trail when you draw a line.

Stir in Parmesan cheese and butter until melted and the sauce is glossy and smooth, then taste and adjust with salt and black pepper. Visual cue: no grainy cheese bits remain and the surface looks shiny.

Slice the rested chicken into thick pieces and return it to the pan. Visual cue: chicken pieces are coated as they rewarm in the sauce.

Toss in the cooked rigatoni and stir to coat evenly. Visual cue: every rigatoni tube appears lightly coated with sauce.

If the sauce feels too thick, loosen it with a splash of reserved pasta water. Visual cue: the sauce loosens to a silky, clingy consistency.

Plate immediately and top with torn fresh basil, extra Parmesan, and a pinch of red pepper flakes. Visual cue: bright green basil and extra cheese sit on top of a creamy red-tinted sauce.