Place potatoes in a microwave-safe bowl with 2 tablespoons water. Cover and microwave on high for 4-5 minutes until just tender when pierced with a knife. This head start ensures they finish at the same time as the shrimp. Drain and set aside.

In a small bowl, whisk together melted butter, minced garlic, 1 teaspoon Cajun seasoning, lemon juice, and Worcestershire sauce.

Tear four 18-inch sheets of heavy-duty foil. Divide par-cooked potatoes, corn pieces, bell pepper, sausage rounds, and shrimp evenly among the four sheets, arranging in the center. Drizzle each with about 2 tablespoons of the garlic butter mixture and sprinkle with remaining 1 teaspoon Cajun seasoning.

Bring the long sides of foil together and fold down tightly in 1-inch folds until sealed against the food. Fold in the short ends twice to seal completely, creating neat rectangular packets. Place seam-side up on a large baking sheet.

Roast at 425°F for 18-22 minutes, until shrimp are pink and opaque and sausage is sizzling. Carefully open one packet to check - shrimp should curl into a loose C shape, not a tight O (which means overcooked).

Open packets carefully - hot steam will escape. Drizzle any remaining garlic butter over the top, sprinkle with fresh parsley, and serve with lemon wedges for squeezing. Serve directly in the foil or transfer to plates.