While your grill preheats, prepare all ingredients for smooth assembly. Trim the asparagus and cut into 2-inch pieces, then set aside. Mince the garlic finely—I find that freshly minced garlic releases more aromatic oils than pre-minced, which really makes a difference in this dish. In a small bowl, combine the softened butter with minced garlic, lemon zest, seafood seasoning, chili flakes, smoked paprika, parsley, salt, and pepper, stirring until well combined. This butter sauce can be made up to a few hours ahead and kept at room temperature.

Heat your grill to 425°F. While it preheats, cut three 18-inch pieces of heavy-duty aluminum foil and lay them flat on your work surface. Divide the shrimp evenly among the three foil sheets, arranging them in a single layer in the center of each piece. Distribute the cut asparagus around the shrimp on each packet. This arrangement allows the heat to circulate evenly around both proteins.

Divide the garlic butter sauce from Step 1 evenly among the three foil packets, spooning it over the shrimp and asparagus. Fold up the sides of each foil piece and crimp the edges tightly to create a sealed packet—I like to double-fold the seams to ensure no steam escapes, which keeps everything moist and infuses the flavors. The sealed packet essentially creates a mini steam chamber for perfectly cooked shrimp.

Place the sealed foil packets directly on the preheated grill grates. Grill for 10 minutes—the shrimp will cook through and turn pink while the asparagus becomes tender-crisp. You don't need to flip the packets; the heat circulates evenly inside the sealed foil.

Remove the foil packets from the grill and let them rest for 1-2 minutes—this allows the shrimp to relax slightly and stay tender. Carefully open each packet (watch out for the hot steam), drizzle with fresh lemon juice, and transfer the contents to serving plates. Serve immediately while everything is still steaming hot.