Prepare for baking: Preheat your oven to 400°F / 200°C.
Line a large, rimmed baking sheet with parchment paper for easy cleanup.
Arrange the shrimp: Pat the shrimp completely dry with paper towels to ensure they roast instead of steam.
Arrange them in a single, even layer on the prepared baking sheet.
Make the garlic butter sauce: In a small bowl, whisk together the melted butter, freshly chopped parsley, minced garlic, salt, and pepper until well combined.
Sauce and bake: Drizzle the garlic butter mixture evenly over the shrimp, tossing gently to coat.
Arrange the lemon slices over and around the shrimp.
Bake for 8 to 10 minutes, or just until the shrimp are pink, firm, and opaque.
Serve immediately: Remove from the oven and serve hot, squeezing some of the roasted lemon juice over the top if desired.
Do not overcook the shrimp! They cook in minutes. As soon as they turn pink and curl into a 'C' shape, they're done. An overcooked shrimp is tough and rubbery.
Don't let that delicious garlic butter go to waste!
Serve with crusty bread, pasta, or zucchini noodles to soak up every last drop of the pan sauce.
