Fill a large pot halfway with water, cover, and place over high heat until it boils.
While you wait for the water to boil, preheat the oven to 400 degrees F and prep all of the ingredients.
Once the water is boiling, add in the potatoes and boil for 8-10 minutes.
Add in the corn and boil for an additional 5 minutes. Drain.
Line a large sheet pan with foil or parchment paper. Spread the corn & potatoes evenly across the pan. Then, distribute the sausage and raw shrimp evenly between the potatoes and corn.
Mix the cajun seasoning & salt into the melted butter and pour over the shrimp boil. Lightly toss with a rubber spatula to distribute the butter.
Bake for 15 minutes, stirring halfway through. Garnish with parsley and green onion. Serve hot & enjoy!