Preheat and prep: Heat your oven to 400°F (200°C).
Lightly grease a 9x13-inch baking dish or line it with parchment for easier cleanup.
Pat the shrimp dry: Use paper towels to remove excess moisture. Dry shrimp brown better and won’t steam, which helps them stay juicy.
Make the garlic-butter mix: In a small bowl, combine melted butter, olive oil, minced garlic, lemon zest, lemon juice, Italian seasoning, paprika, and red pepper flakes. Season with a good pinch of salt and pepper.
Toss with Parmesan: In a larger bowl, add the shrimp. Pour over the garlic-butter mixture and toss.
Sprinkle in the Parmesan and panko (if using). Toss again until everything is evenly coated.
Arrange in the dish: Spread the shrimp in a single layer in the baking dish. Overcrowding leads to uneven cooking, so keep them snug but not piled.
Bake: Place on the center rack and bake for 8–10 minutes, depending on shrimp size. They’re done when opaque and just firm to the touch. Do not overbake.
Broil for a minute (optional): For a lightly crisp top, switch to broil for 1–2 minutes.
Watch closely to avoid burning the garlic or cheese.
Finish and serve: Sprinkle with fresh parsley and extra Parmesan. Serve hot with lemon wedges for squeezing over the top.