Add olive oil, onion and smoked sausage to the bottom of an electric pressure cooker on the BROWN/SAUTE function. Cook about 5 minutes until the onions start to soften and the sausage starts to render off some fat.
Add in pasta, diced tomatoes, cajun seasoning, salt and water. Stir and press pasta down into an even layer across the top of the pressure cooker. Add lid, secure, and switch cooking function to BEANS/CHILI, and cook for 5 minutes under HIGH pressure.
Once timer is complete, quick release pressure and stir pasta.
Add in heavy cream, parmesan cheese and cream cheese and continue to stir until its all melted in and created a creamy sauce. Top with parsley flakes and serve.
*I don't use a ton of cajun seasoning because it's a little on the spicy side. Feel free to add more if you can handle the spice. I have kids, so milder is better.