For the Crust and Vegetable Base

• 1 (9-inch) deep-dish pie crust
  Store-bought or homemade, unbaked. A deep-dish crust gives enough room for the filling and topping.
• 2 tablespoons unsalted butter
  For sautéing the vegetables and building flavor.
• ½ cup finely chopped onion
  Yellow or sweet onion works beautifully.
• ½ cup finely chopped red bell pepper
  Adds color, sweetness, and a subtle crunch.
• ¼ cup finely chopped celery (optional but recommended)
  Gives a classic savory backbone, similar to chowder.
• 2 cloves garlic, finely minced
  For a deep, aromatic flavor that pairs perfectly with shrimp.

For the Shrimp Filling

• 1½ pounds large shrimp (16–20 count), peeled and deveined, tails removed, roughly chopped
  Fresh or thawed frozen shrimp work; chopping them helps distribute them through the filling.
• 2 tablespoons all-purpose flour
  Helps thicken the creamy mixture so the pie slices neatly.
• 1 cup milk or half-and-half
  Creates a silky base; you can also use a mix of whole milk and cream.
• ½ cup heavy cream
  For extra richness and a velvety texture.
• 1 teaspoon Old Bay seasoning
  Brings the classic seafood flavor with a hint of spice.
• ½ teaspoon garlic powder
  Boosts the garlic flavor without overpowering.
• ½ teaspoon smoked paprika (optional)
  Adds a gentle smoky note that complements shrimp.
• ¼ teaspoon cayenne pepper (optional)
  For a little heat; adjust to taste.
• ½ teaspoon salt, or to taste
• ¼ teaspoon freshly ground black pepper
• 1 tablespoon lemon juice
  Brightens the filling and balances the richness.
• ¼ cup freshly grated Parmesan cheese
  Adds saltiness and depth.
• ½ cup shredded cheese, such as cheddar, Monterey Jack, or a blend
  For extra creaminess and a lightly cheesy flavor.
• 2 large eggs, lightly beaten
  Help the filling set into a custard-like texture that holds its shape when sliced.
• 2 tablespoons chopped fresh parsley or chives
  For freshness, color, and a gentle herbal note.

For the Crispy Panko Topping

• ¾ cup panko breadcrumbs
  Give the topping a light, crunchy texture.
• 3 tablespoons unsalted butter, melted
  Helps the topping brown and crisp in the oven.
• 2 tablespoons grated Parmesan cheese
  Adds a savory punch and helps the topping cling together.
• ½ teaspoon Old Bay seasoning
  Ties the flavor of the topping to the filling.
• 1 tablespoon chopped fresh parsley or chives
  For color and a fresh finish.