Cook pasta al dente, according to package directions.
Meanwhile, season the shrimp with some paprika, onion powder, garlic powder and low salt Cajun seasoning.
Pan sear the shrimp for about 5 minutes with olive oil until they are almost cooked through. Set aside.
In the same pan, sauté the onion until they are caramelized.
Add in the spices, pasta water and heavy cream.
Simmer on low for about 5 minutes and then add in the grated parmesan cheese. Give it a stir and then simmer for another minute or so.
Add in the cooked pasta and toss to coat really well with the creamy Cajun sauce.
Then add in the shrimp and mix everything together well. Cover and simmer for 3-4 minutes on low heat. Remove and serve!
You can garnish with some pepper flakes or chopped parsley before serving.