In a saucepan, heat the olive oil and sauté the onions until translucent. Add in garlic and tomatoes. Stir until the tomatoes begin incorporating into the sauce.
Add in cayenne pepper powder, Cajun seasoning, and cream cheese. Stir until the cheese is melted.
Add in the chicken stock, heavy cream, and Parmesan cheese. Continue stirring until the Parmesan has melted.
Remove from heat and using a blender or food processor, pulse blend the sauce until smooth.
Pour the sauce back into the saucepan and heat until the sauce is thickened to your preferred consistency.