Add water about 2/3 full to a large saucepan and add salt.
Put the water for the pasta on to boil and start preparing your other ingredients.
Cut chicken breasts into bite-sized pieces and set aside.
Add olive oil to a large frying pan on medium heat.
Add chopped onions to frying pan and sauté with olive oil.
Sauté the onions in the olive oil until they start to get brown and translucent.
Add butter to the frying pan and let it melt.
Add the minced garlic to the frying pan and sauté until the garlic is fragrant.
Generously season chicken breasts with salt and pepper.
Add the chicken to the frying pan with Italian seasoning and red pepper flakes.
Sauté chicken until cooked through and starting to brown.
At this point, your pasta should probably start to boil. Follow instructions on the box for al dente pasta.
Add heavy whipping cream and sun-dried tomatoes to the frying pan with the chicken.
Bring to a simmer and cook until sauce has thickened, about 2-3 minutes.
Turn down heat and add grated parmesan cheese to the frying pan. Reserve 1/4 cup of the parmesan for adding to the dish at the end.
Stir the parmesan into the sauce until melted. Taste and add more salt and pepper if needed. I added 1/2 teaspoon of salt and 1/4 teaspoon of pepper. Remove from heat.
Drain pasta when finished cooking.
Add pasta to a large serving bowl or pasta bowl.
Pour the sauce over the pasta and stir until combined. Garnish pasta with basil and the rest of the grated parmesan cheese.
Serve and enjoy.