Slice smoked sausage into rounds. Heat oil in large skillet over medium-high heat. Add sausage slices in single layer without crowding. Cook without moving until deep brown on both sides. Remove browned sausage and set aside.

Add more oil to the same skillet if needed. Sauté diced onions until softened and translucent. Add sliced bell peppers and cook until slightly tender. Stir in minced garlic and cook until fragrant. Season vegetables with half the cajun seasoning.

Add uncooked pasta to the skillet. Pour in chicken broth and bring to a boil. Stir occasionally to prevent sticking. Cook until pasta is almost al dente. The pasta will finish cooking in the cream sauce.

Reduce heat to medium-low before adding cream. Pour in heavy cream slowly while stirring. Add remaining cajun seasoning and paprika. Return browned sausage to the skillet. Stir in grated parmesan cheese until melted and sauce thickens. Simmer gently until sauce coats pasta perfectly.

Taste and adjust seasoning with salt, pepper, or more cajun spice. Stir in fresh chopped parsley. Add splash of pasta water if sauce gets too thick. Let rest for 2-3 minutes before serving. Garnish with extra parmesan and red pepper flakes if desired.