Preheat your grill to medium-high heat or 400 degrees F.
Set a large cast-iron pan on the grill grates to warm up, about 1-2 minutes.
Next, add olive oil to the skillet and the minced garlic (or shallot). Sauté 15-20 seconds until it becomes fragrant.
Add the cubed unsalted butter and Worcestershire sauce. Cook for 1 minute or until butter has melted.
Next, stir in the beer (white wine or vegetable broth) in the skillet. Simmer ingredients for 2 minutes or until it starts to reduce.
Add Voodoo Seasoning (or bottled Cajun seasoning), minced rosemary, black pepper, a pinch of salt, and Louisiana-style hot sauce. Stir through.
Nestle the peeled and deveined shrimp into the sauce. Cook for about 3-4 minutes until the shrimp turns pink and opaque. Turn them over halfway through the cooking to ensure they are well coated in the sauce.
While the shrimp is cooking, brush the halved lemons with a little olive oil and grill them cut side down for 1-2 minutes or until slightly charred. See the recipe photo for guidance.
Remove the skillet from the grill, and arrange the lemons in with the shrimp. Garnish with chopped parsley before serving.
Serve this dish over cooked rice, pasta, or with a heel of crusty French bread to sop up all that flavorful sauce. Give your guest the option of squeezing lemon juice over their portion.
Store leftover Louisiana BBQ shrimp in an airtight container in the refrigerator for 2 days. Reheat in a skillet on the stovetop.