Seafood Casserole is a rich, comforting, and elegant baked dish featuring a delicious combination of shrimp, scallops, fish, mussels, and crab meat nestled in a creamy garlic herb sauce and topped with a golden, crispy Parmesan breadcrumb crust. This Mediterranean-inspired casserole is perfect for family dinners, holiday gatherings, or special occasions when you want an impressive seafood meal with minimal effort.

The creamy sauce, tender seafood, aromatic herbs, and crispy topping create a balanced dish that pairs beautifully with rice, roasted vegetables, pasta, or crusty bread.

Why You'll Love This Recipe

  • Rich, creamy, and satisfying
  • Loaded with a variety of seafood
  • Restaurant-quality meal made at home
  • Perfect for holidays and entertaining
  • Crispy golden Parmesan topping
  • Easy to customize with your favorite seafood
  • Ready in about one hour
  • Great make-ahead dinner

What is Seafood Casserole?

Seafood Casserole is a baked seafood dish made with a variety of seafood combined in a creamy garlic and herb sauce, then topped with seasoned breadcrumbs and Parmesan cheese before baking until golden and bubbly.

Common seafood choices include:

  • Shrimp
  • Scallops
  • White fish
  • Crab meat
  • Mussels
  • Clams
  • Lobster (optional)

The result is a luxurious casserole with tender seafood, creamy sauce, and a crisp, flavorful topping.

Ingredients

For the Seafood

  • 300 g (10 oz) shrimp, peeled and deveined
  • 250 g (9 oz) sea scallops
  • 300 g (10 oz) firm white fish (such as cod, haddock, or halibut), cut into bite-sized pieces
  • 200 g (7 oz) lump crab meat, picked over for shells
  • 200 g (7 oz) cooked mussels or clams (optional)
  • 1 tablespoon lemon juice
  • Salt and freshly ground black pepper, to taste

For the Cream Sauce

  • 2 tablespoons unsalted butter
  • 2 tablespoons extra virgin olive oil
  • 1 small onion, finely diced
  • 4 garlic cloves, minced
  • 2 tablespoons all-purpose flour
  • 1½ cups seafood stock or fish stock
  • 1 cup heavy cream
  • ½ cup grated Parmesan cheese
  • 1 teaspoon Dijon mustard
  • 1 teaspoon fresh thyme leaves
  • 1 tablespoon chopped fresh parsley
  • ½ teaspoon smoked paprika
  • ½ teaspoon sea salt
  • ½ teaspoon freshly ground black pepper

Crispy Topping

  • 1 cup panko breadcrumbs
  • ¼ cup grated Parmesan cheese
  • 2 tablespoons melted butter
  • 1 tablespoon chopped parsley
  • ½ teaspoon garlic powder
  • ½ teaspoon paprika

Garnish

  • Fresh parsley
  • Lemon wedges
  • Extra Parmesan cheese
  • Chopped chives

Kitchen Equipment

  • 9 × 13-inch baking dish
  • Large skillet
  • Mixing bowls
  • Whisk
  • Wooden spoon
  • Measuring cups and spoons

Preparation Time

  • Prep Time: 20 minutes
  • Cook Time: 35 minutes
  • Total Time: 55 minutes

Serves: 6

Step 1: Prepare the Seafood

Pat all seafood dry with paper towels.

Season lightly with:

  • Salt
  • Black pepper
  • Lemon juice

Set aside while preparing the sauce.

Step 2: Make the Cream Sauce

Preheat the oven to 190°C (375°F).

In a large skillet, heat the butter and olive oil over medium heat.

Add the onion and cook for 5 minutes, until softened.

Stir in the garlic and cook for 30 seconds until fragrant.

Sprinkle in the flour and whisk continuously for 1–2 minutes to create a roux.

Gradually whisk in the seafood stock until smooth.

Add:

  • Heavy cream
  • Dijon mustard
  • Parmesan cheese
  • Thyme
  • Parsley
  • Smoked paprika
  • Salt
  • Black pepper

Simmer gently for 5–7 minutes, stirring until the sauce thickens.

Step 3: Assemble the Casserole

Lightly grease the baking dish.

Arrange the seafood evenly in the dish.

Pour the warm cream sauce over the seafood, ensuring everything is evenly coated.

Gently stir if needed to distribute the seafood.

Step 4: Prepare the Topping

In a small bowl, combine:

  • Panko breadcrumbs
  • Parmesan cheese
  • Melted butter
  • Parsley
  • Garlic powder
  • Paprika

Mix until evenly combined.

Sprinkle the topping evenly over the casserole.

Step 5: Bake

Bake uncovered for 25–30 minutes, or until:

  • The seafood is cooked through.
  • The sauce is bubbling.
  • The topping is golden brown and crisp.

If the topping needs more color, broil for the final 1–2 minutes, watching carefully to prevent burning.

Step 6: Rest

Allow the casserole to rest for 5 minutes before serving so the sauce can settle slightly.

Step 7: Serve

Garnish with:

  • Fresh parsley
  • Chopped chives
  • Extra Parmesan
  • Lemon wedges

Serve hot.

Flavor Profile

This Seafood Casserole features:

  • Tender, juicy seafood
  • Rich, creamy garlic sauce
  • Nutty Parmesan
  • Fresh herbs
  • Crisp golden breadcrumb topping
  • Bright citrus finish
  • Mild smoky paprika

Best Side Dishes

Serve Seafood Casserole with:

  • Garlic bread
  • Crusty sourdough bread
  • Buttered rice
  • Lemon herb rice
  • Roasted baby potatoes
  • Steamed asparagus
  • Green beans
  • Roasted broccoli
  • Caesar salad
  • Mediterranean mixed salad

Tips for Perfect Seafood Casserole

Use Fresh Seafood

Fresh seafood provides the best flavor and texture, but high-quality frozen seafood that has been fully thawed and patted dry also works well.

Avoid Overcooking

Seafood cooks quickly. Baking just until the fish flakes easily and the shrimp turn opaque helps keep everything tender.

Dry the Seafood

Removing excess moisture prevents the sauce from becoming watery.

Use Fresh Parmesan

Freshly grated Parmesan melts more smoothly and provides better flavor than pre-grated varieties.

Let It Rest

Allowing the casserole to rest for a few minutes after baking helps the sauce thicken slightly, making it easier to serve.

Delicious Variations

Lobster Seafood Casserole

Add chunks of cooked lobster tail for an extra luxurious version.

Mediterranean Seafood Casserole

Stir in chopped spinach, sun-dried tomatoes, olives, and crumbled feta cheese before baking.

Spicy Seafood Casserole

Add cayenne pepper, crushed red pepper flakes, or diced jalapeños for a gentle kick.

Mushroom Seafood Casserole

Sauté sliced mushrooms with the onions for added earthy flavor.

Gluten-Free Version

Use gluten-free flour for the roux and gluten-free breadcrumbs for the topping.

Storage

Store leftover casserole in an airtight container in the refrigerator for up to 2 days.

Freezing is not recommended because the cream sauce may separate and the seafood can become overcooked when reheated.

Reheating

Reheat in a 170°C (340°F) oven for 15–20 minutes, covered loosely with foil.

Avoid overheating to maintain the seafood's tender texture.

Nutrition (Approximate Per Serving)

  • Calories: 470
  • Protein: 36 g
  • Fat: 27 g
  • Carbohydrates: 18 g
  • Fiber: 1 g
  • Sugar: 3 g
  • Sodium: 690 mg

Nutritional values are approximate and may vary depending on the seafood and ingredients used.

Frequently Asked Questions

Can I use frozen seafood?

Yes. Thaw it completely in the refrigerator and pat it dry before adding it to the casserole to avoid excess moisture.

Can I prepare this casserole ahead of time?

Yes. Assemble the casserole (without the breadcrumb topping), cover, and refrigerate for up to 24 hours. Add the topping just before baking.

What fish works best?

Firm white fish such as cod, haddock, halibut, pollock, or sea bass hold their shape well during baking.

Can I make this casserole without cream?

Yes. Replace the heavy cream with evaporated milk or a mixture of milk and a little extra flour for a lighter version.

How do I know when the seafood is fully cooked?

The fish should flake easily with a fork, shrimp should be opaque and pink, and scallops should be firm yet tender.

Final Thoughts

Seafood Casserole is a comforting and elegant baked dish that combines a medley of tender seafood with a creamy garlic herb sauce and a crispy Parmesan breadcrumb topping. Rich in flavor yet simple to prepare, it's an excellent choice for everything from cozy family dinners to festive holiday meals. Serve it with crusty bread, rice, or roasted vegetables for a complete Mediterranean-inspired feast that's sure to impress every seafood lover.