Prepare the prawns: Rinse the prawns under cold running water and pat them dry with paper towels. Using a sharp knife, carefully split each prawn open along the back, keeping the shell intact. Remove the vein and discard. This step helps the prawns cook evenly and allows the garlic butter to infuse deeply into the meat.
Make the garlic herb butter: In a small mixing bowl, whisk together the melted butter, olive oil, minced garlic, lemon juice, lemon zest, chopped parsley, Italian herbs, salt, and black pepper. The mixture should be aromatic and slightly thickened, ready for basting.
Preheat the grill: Heat your outdoor grill or grill pan to medium-high. Lightly oil the grates to prevent sticking. The high heat will help achieve a beautiful char on the shells while keeping the prawn meat juicy.
Grill the prawns: Brush each prawn generously with the garlic herb butter, making sure the inside flesh is well coated. Place the prawns shell-side down on the grill. Cook for 4–5 minutes, then flip carefully and grill for another 2–3 minutes until the shells turn bright orange-red and the meat becomes opaque. Baste with additional garlic butter as they cook for maximum flavor.
Finish and serve: Transfer the grilled prawns to a serving platter. Drizzle any remaining garlic herb butter over the top, and sprinkle with extra chopped parsley and a pinch of sea salt. Serve immediately with lemon wedges for squeezing — the citrus cuts through the richness and enhances the smoky, buttery flavor.
