Rinse the shrimp under cold water and pat dry. If not already peeled, peel shells leaving tails on if preferred. Scrub the potatoes and cut any larger ones in half so pieces are roughly uniform. Cut the corn into 2–3 pieces each. Smash the garlic cloves with the flat side of a knife. Cut the lemon in half; reserve one half for boiling and slice the other half for serving.

Bring Broth to a Boil

In a large pot (big enough to hold 3 liters), add 3 liters of water, 2 tablespoons kosher salt, 2 tablespoons Old Bay (or seafood boil seasoning), bay leaves, and the smashed garlic. Squeeze the juice of one lemon half into the water and drop that half into the pot. Bring the mixture to a vigorous boil over high heat.

Cook Potatoes

Once the water is boiling, add the potatoes. Boil for 10–12 minutes, or until a paring knife or fork slips into the potatoes with only slight resistance.

Add Corn

Add the corn pieces to the pot with the potatoes and continue boiling for 5–7 minutes, until corn is heated through and potatoes are tender.

Add Shrimp

Add the 3/4 lb shrimp to the pot and boil for 2–3 minutes, or until shrimp turn pink and opaque. Shrimp cook quickly — do not overcook. If using larger shrimp, cook on the shorter side to avoid toughness.

Drain and Finish

Turn off heat and carefully drain the pot through a colander. Return the drained shrimp, potatoes, and corn to the pot (off heat) or to a large bowl. Immediately add 3 tablespoons unsalted butter, 2 tablespoons chopped fresh parsley, 1 teaspoon black pepper, and optional 1 teaspoon cayenne if you like heat. Toss gently so butter melts and coats everything. Taste and add a pinch of salt or additional seasoning if needed. Squeeze the remaining lemon half over the dish and toss once more.

Serve

Serve hot on a platter or individual plates. Provide extra lemon slices, melted butter or drawn butter if desired, and napkins. Portion is 3/4 lb seafood with corn and potatoes per serving.