Preheat the oven: Arrange two racks in the bottom-third of the oven and the top-third of the oven. Preheat oven to 425℉ / 218℃.
Butterfly the shrimp: Butterfly 1 ½ pounds colossal shrimp. To do so, use a sharp knife to make a deep incision lengthwise through abdomen of the shrimp (do not slice all the way through). Gently flatten and splay open, like a book, leaving the tails intact.TIP: To test if you've made a deep enough incision, firmly place the shrimp on a plate, splayed side down. It should be able to stand upright without falling down (it's okay if the tail flails a little bit).
Season: Toss the shrimp with 1 teaspoon Diamond Crystal Kosher Salt, a pinch of black pepper, 2 cloves garlic (finely grated), and 1 tablespoon extra-virgin olive oil. Set aside.
Make the breadcrumbs: In a small bowl, grate the zest from 1 lemon. Add ½ cup panko breadcrumbs, ¼ cup flat-leaf parsley, and stir to combine.Set a small saucepan with the remaining tablespoon of olive oil and 2 tablespoons unsalted butter over medium heat. Once the butter is melted, add 1 ½ teaspoons dried oregano, ½ teaspoon red pepper flakes, and saute until sizzling about 1 minute. Toss with the breadcrumbs, and season with a pinch of salt, to taste.
Arrange: Arrange the shrimp in a single layer in an oval baking pan (or casserole dish), starting around the edges of the pan and working your way towards the center.Place each shrimp with the cut side down in the pan, allowing the tails to curl upwards (it's okay if the tails flail a bit from side to side). Drizzle 2 tablespoons dry white wine evenly over the shrimp.TIP: Uncooked shrimp can be floppy, especially the tails, making assembly tricky. To help them stand up, pair two shrimp together by tucking one tail into the crevice of the other for support. Adjust them in the pan as needed until you're happy with the arrangement. The tails will firm up during cooking, making them more upright.
Assemble: Sprinkle breadcrumbs evenly over the body of each shrimp, and add any extra breadcrumbs to the center of the pan as desired.TIP: Depending on the size of the shrimp (and your pan), you may not need to use all of the breadcrumbs.
Bake: Bake on the bottom-third rack until the shrimp are firm, opaque, and pink, about 10 - 15 minutes. If desired, move the pan to the top rack and broil for 30 seconds - 1 minute until the breadcrumbs are golden brown. Keep a close eye during broiling to prevent burning.Remove from the oven and allow to cool slightly for a few minutes before serving. Serve with lemon wedges and crusty bread.
Notes
Colossal shrimp: Colossal shrimp are large (even larger than jumbo!) shrimp, usually about 12 - 15 count. It's important to get the large size so that they're easy to stuff and easy to eat!TIP: Look for shell-on, deveined shrimp to minimize prep work.Storage: This dish is best enjoyed day of, so I recommend making a smaller batch if you don't think you can finish it all in one day! That said, leftovers can be stored in an airtight container for 3 - 4 days. Reheat in the casserole dish, wrapped in foil, for about 8 - 10 minutes in the oven at 350°F.