Step 1

Finely chop 6 garlic cloves. Transfer half to a 9x13-inch or other 3-quart baking dish; reserve the remaining for the garlic butter. Finely grate the zest of 1 medium lemon into the baking dish. Add 1 tablespoon olive oil, 1 teaspoon of the kosher salt, 1/4 teaspoon black pepper, and 1/4 teaspoon red pepper flakes, and stir to combine.

Step 2

Clean and devein 1 1/2 pounds extra-jumbo shrimp, leaving the tails intact if desired. Add the shrimp to the baking dish and toss to coat in the garlic mixture. Marinate in the refrigerator for 20 minutes.

Step 3

Meanwhile, arrange a rack in the middle of the oven and heat the oven to 400°F. Cut the zested lemon in half, then cut the remaining medium lemon into wedges and reserve for serving. Pick the leaves from 1 small bunch fresh parsley until you have 1/4 cup, then coarsely chop. Make the garlic butter.

Step 4

Melt 4 tablespoons unsalted butter in a small saucepan over medium heat. Continue to cook until it just starts to turn golden, about 2 minutes. Add the reserved garlic and squeeze the juice from the zested lemon into the butter. It may bubble up. Cook until the garlic is tender, about 1 minute more. Add the remaining 1/2 teaspoon kosher salt and stir to combine. Remove the saucepan from the heat and let cool slightly but not until solidified.

Step 5

Scrape the lemon-garlic butter over the shrimp and toss to combine. Bake until the shrimp are opaque and just cooked through, 8 to 10 minutes. Garnish with the parsley and serve with the lemon wedges.