Cooking the Pasta

1. Bring a large pot of salted water to a boil.
2. Cook pasta according to package directions until al dente (usually 1-2 minutes less than indicated cooking time).
3. Reserve 1 cup of pasta water before draining – this starchy water is liquid gold for adjusting sauce consistency later.
4. Drain pasta but do not rinse – the starch helps the sauce adhere better.

Preparing the shrimp

1. Heat olive oil in a large, deep skillet or Dutch oven over medium-high heat.
2. Add seasoned shrimp in a single layer, being careful not to overcrowd (cook in batches if necessary).
3. Sear for just 1-2 minutes per side until pink and barely cooked through – they’ll finish cooking in the sauce later.
4. Remove shrimp to a plate and set aside.
5. In the same pan, add sliced andouille sausage and cook for 2-3 minutes until browned on both sides.
6. Transfer sausage to the plate with shrimp.

Creating the Cajun Sauce

1. Reduce heat to medium and add butter to the pan.
2. Add diced onion and bell pepper, sautéing for 3-4 minutes until softened.
3. Add minced garlic and white parts of green onions, cooking for 1 minute until fragrant.
4. Sprinkle flour over vegetables and stir constantly for 1 minute to cook out the raw flour taste.
5. Slowly whisk in chicken broth, scraping up any browned bits from bottom of pan.
6. Pour in heavy cream, remaining Cajun seasoning, thyme, oregano, and cayenne pepper.
7. Bring to a gentle simmer (don’t boil) and cook for 3-4 minutes until slightly thickened.
8. Stir in Parmesan cheese until melted and smooth.

Bringing It All Together

1. Return shrimp and sausage to the pan, including any accumulated juices.
2. Add cooked pasta directly to the sauce, tossing gently to coat.
3. If sauce is too thick, add reserved pasta water a few tablespoons at a time.
4. Cook for 1-2 minutes until everything is heated through and shrimp are fully cooked.
5. Taste and adjust seasoning with salt and pepper as needed.
6. Garnish with reserved green onion tops before serving.