Boil pasta in salted water until al dente. Reserve 1/2 cup water, drain, and set aside.

In a large skillet, brown the sliced Andouille sausage over medium-high heat. Remove and set aside.

Add 1 tbsp butter to the skillet. Sear shrimp (and crawfish) with a pinch of Cajun spice until pink. Remove and set aside.

Add remaining butter and veggies (peppers, mushrooms) to the pan. Sauté until soft. Add garlic and cook 1 minute.

Pour in heavy cream, marinara, and seasonings. Simmer 5-7 minutes until slightly thickened.

Stir in parmesan cheese until melted. Add salt and pepper to taste.

Return pasta, sausage, and seafood to the pan. Toss to coat evenly.

Garnish with green onions and serve hot.