Pour 2 Tbsp. olive oil over chicken breasts and sprinkle with 2 Tbsp. of Cajun seasoning.  (Feel free to use more or less seasoning)

Cook pasta according to package directions in a big pot. Drain when done.

While the pasta is cooking, put a tablespoon of olive oil in a grill pan and heat until medium-hot. Add the chicken and cook about 4-5 minutes on each side until done. (Timing will depend on thickness of chicken so test to make sure they are cooked thoroughly) Cut into strips and keep warm until pasta and sauce are finished.

Melt butter in a medium saucepan over medium heat. Add garlic and whisk frequently to ensure the garlic does not burn, 2 minutes.

Gradually whisk in 2 cups of the heavy cream and 1 cup of the parmesan.  Add 1 tbsp. of Cajun seasoning and continually whisk. Add in the remaining heavy cream and parmesan a little at a time, tasting and monitoring along the way to make sure the mixture is not too runny or too thick. It should be the consistency of an alfredo sauce.  

You can either serve the noodles in a dish/bowl with the sauce and chicken on top; combine the noodles and sauce then place the chicken on top; combine the sauce, noodles, and chicken to serve.