Baked New England Seafood Casserole Recipe
Try this New England Seafood Casserole for a crowd pleasing, elegant dish that’s so easy to make. It’s loaded with a combination of fresh seafood and topped with a golden brown cracker crust.
If you’re looking for the best seafood casserole recipe, this classic Baked New England Seafood Casserole delivers every time.
Tender shrimp, scallops, and flaky white fish are folded into a rich, creamy sauce kissed with Dijon and sherry, then topped with buttery cracker crumbs and baked until golden and bubbling. It’s comforting without being heavy, elegant without being fussy – and surprisingly simple to pull together.
Whether you’re planning a cozy Sunday dinner or hosting friends, this casserole fits right in — the same way my French Onion Chicken has become a go-to when I want something comforting but just a little elevated.
And yes – it’s earned its spot as a reader favorite for a reason!
The Dish Details
The combination of mixed seafood creates balanced texture, while a lightly thickened cream sauce enhances the natural flavor of the seafood. The buttery cracker topping adds contrast and that nostalgic New England charm.
- Flavor: Creamy, savory, lightly briny with a subtle tang from Dijon
- Texture: Tender seafood under a buttery, golden cracker crust
- Difficulty: Straightforward — no complicated techniques
- Occasion: Holiday dinners, dinner parties, cozy winter meals
- Make-Ahead Friendly: Assemble ahead, bake just before serving
If you love creamy seafood bakes, this scallop gratin dish is another must try!
Gather Your Ingredients
They key to making this a ‘New England’ casserole is sourcing seafood from the coastal waters of that region. Whenever possible, purchase wild caught for sustainability + great flavor. When fresh isn’t available, wild caught frozen is perfect.
- Sea scallops — look for dry or dry pack for a sweet, fresh flavor. ‘Wet’ scallops have been treated with a solution which helps to preserve them, but then they also retain a lot of water weight (which you pay for) and can impact the flavor.
- Raw shrimp — large or jumbo size will cook perfectly within the provided baking time.
- Cod — a firm white fish, but other varieties can stand in. (More on that in Substitutions below!)
- Cooking fats — olive oil and unsalted butter.
- Aromatics — shallots and garlic.
- Produce — brown mushrooms and fresh parsley.
- All purpose flour — to help thicken the sauce.
- Dry sherry — a fortified wine with a slight nutty quality, and brings a distinct flavor to the sauce.
- Dijon mustard — just a little to provide a tangy bite to the sauce.
- Heavy cream — for a silky sauce.
- Ritz crackers — you just gotta have a crumbled cracker topping for that throwback vibe. We keep the whole wheat version on hand, but original is good, too.
- Kosher salt + fresh cracked black pepper — or coarse sea salt instead of kosher.
Seafood Substitutions
You certainly aren’t limited to using the types of seafood I suggest in this recipe. In fact, if you find a good price for any of your favorite fruits of the sea, sub them in. The main thing to keep in mind is cooking time. The thickness and texture of the seafood will impact how long each needs to cook.
- When to precook fish — a firm, denser textured fish may require precooking (just a minute or two on each side). Thin fillets with more delicate textures do not need to be precooked.
- When to cut small or leave as whole fillets — thin, delicate fish fillets can be left whole and laid in the bottom of the casserole dish before adding the other seafood. Thick, firm fillets can be cut into smaller portions.
Other types of fish you could use instead of cod include haddock, flounder, sole, halibut…to name a few. You can also include lump crab meat and lobster. With lobster meat, no need to precook, but if using tail meat, do cut it into smaller pieces.
Other Ingredient Substitutions + Variations
- Shallots — use red onion or sweet onion.
- Mushrooms — you can omit, or sub in veggies like green pepper, celery, or peas.
- Parsley — consider other garnishes like chives, fresh dill or green onion.
- Dry sherry — swap with dry white wine, fish stock or chicken broth.
- Ritz crackers — instead, use panko bread crumbs or grated parmesan cheese, or a combo!
How To Make Baked Seafood Casserole
- Distribute scallops and shrimp across the bottom of a lightly buttered baking dish.
- Heat butter and olive oil in a nonstick skillet over medium heat. Briefly sauté pieces of cod in the skillet, then nestle them among the other seafood in the casserole dish. Season with salt + pepper.
- Cook the shallots, garlic and mushrooms in the skillet until tender, then add the flour.
- Whisk in the sherry, mustard and cream. Season, then pour over the seafood. Sprinkle with parsley.
- Combine cracker crumbs with the remaining butter and distribute over the whole dish. Bake for 15 minutes in a 400°F preheated oven.
Make-Ahead, Storage & Reheating Tips
Make-Ahead – You can absolutely assemble this casserole in advance. Prepare everything except the cracker topping, cover tightly, and refrigerate for up to 24 hours. Mix and add the cracker crumb topping just before baking to keep it crisp. Since the casserole will be cold from the refrigerator, plan to add a few extra minutes to the bake time until it’s hot and bubbling in the center.
Storage & Reheating – Leftovers are surprisingly delicious. The flavors settle in and deepen a bit overnight. Transfer any remaining casserole to an airtight container and refrigerate for up to 2 days. To reheat, warm individual portions in the microwave in short intervals until just heated through. For larger portions, place in an oven-safe dish, cover with foil, and reheat at 350°F until hot. For best texture, avoid overcooking during reheating – seafood can turn rubbery if overheated.
What to Sip
No surprise here… wine. But you’ve got options:
- A dry, crisp white like Sauvignon Blanc keeps things bright and lets the seafood shine. If you prefer something a touch softer, an off-dry Riesling plays beautifully with the natural sweetness of shrimp and scallops.
- And if you want to lean into coastal vibes? Albariño is especially lovely with shellfish – it’s fresh, slightly briny, and feels like it belongs next to a bubbling seafood casserole.
- If you’d rather skip the wine, sparkling water with lemon or a light citrus-forward cocktail works beautifully here too. Keep it clean and refreshing.
What to Serve with Seafood Casserole
This baked seafood casserole is rich and creamy, so I like to balance it with something green or herby – or go all in and build a cozy, dinner-party-style plate.
- Keep It Fresh & Green – Foil Packet Grilled Asparagus is bright, simple, and won’t fight for oven space. Easy Haricots Verts are tender-crisp and elegant without trying too hard.
- Add Something Herby – Herby Baby Roasted Potatoes have crispy edges, fluffy centers, and are perfect for soaking up that creamy sauce.
- Lean Into Cozy – Creamed Spinach Casserole is perfect if you’re going full comfort mode. Want more creamy on creamy? Roasted Garlic Mashed Potatoes is an absolute must.
If you’re entertaining, this casserole plus one green vegetable and one potato side feels complete, thoughtful, and quietly impressive — no overthinking required.
Frequently Asked Questions
A mix of shrimp, scallops, and firm white fish (like cod or haddock) gives the best balance of flavor and texture. The variety keeps the casserole interesting and prevents it from feeling one-note. Check out the Seafood Substitutions above for more ideas.
Yes. Assemble the casserole up to 24 hours in advance, cover tightly, and refrigerate. Add the cracker topping just before baking for the best texture.
For this recipe, larger pieces (like fillets) are par-cooked, so they finish at the same rate as smaller, quicker cooking types of seafood (like shrimp or scallops). Bake just until the centers are opaque. See the Seafood Substitutions section above for tips on when to pre-cook or when to cut pieces smaller.
More Seafood Favorites!
- Sautéed White Fish + Broccolini Over Creamy Mascarpone Polenta
- Shrimp + Polenta Appetizer with Calabrian Cream
- Grilled Salmon Salad with Pistou
- Lobster Mac + Cheese
- Check out all my seafood recipes!
New England Seafood Casserole
Ingredients
- 3½ tablespoon unsalted butter, divided
- 12 sea scallops
- 1 pound shrimp, large or jumbo, peeled + deveined
- 1 tablespoon olive oil
- ¾ pound cod fillet, cut into 2-inch pieces
- kosher salt + fresh cracked black pepper
- 1 large shallot, minced
- 3 cloves garlic, minced
- 4 ounce cremini mushrooms, sliced
- 1 tablespoon all purpose flour
- ¼ cup dry sherry
- 1 tablespoon Dijon mustard
- ½ cup heavy cream
- 3 tablespoon flat leaf parsely, minced
- 8 Ritz crackers, crushed into crumbs
Instructions
- Preheat the oven to 400°F. Butter a 9-by-13-inch baking dish with 1/2 tbsp of butter. Distribute the scallops and shrimp across the bottom of the dish.
- Heat 1 tablespoon of butter and the olive oil in a nonstick skillet over medium heat until hot and bubbly. Sauté the pieces of cod for two minutes on each side. Transfer to the casserole, distributing the pieces among the scallops and shrimp. Season with kosher salt and fresh cracked pepper.
- Add shallots to the skillet; sauté for 3 to 4 minutes to soften. Add the garlic and cook for another minute. Add the mushrooms and 1 tablespoon of butter. Season with salt + pepper; sauté for 4 to 5 minutes. Add the flour and cook for one more minute, stirring continuously. Turn the heat down to medium-low.
- Whisk in the sherry, Dijon mustard and heavy cream all at once. Cook for a minute or two to thicken. Season with salt + pepper to taste. Pour the sauce over the seafood and sprinkle with parsley. (If the sauce seems thick and like it won't cover the casserole, don't worry. Spread it as evenly as possible. As the seafood bakes, it will release juices and mix with the sauce.)
- Melt the remaining tablespoon of butter and combine with the cracker crumbs. Distribute over the top of the casserole. Bake for 15 to 20 minutes. (The internal temperature of the cod should read 145°F.)
Notes
- Selecting seafood: Whenever possible, purchase wild caught seafood for sustainability and great flavor. When fresh isn’t available, wild caught frozen is perfect.
- Reheating: Place remaining casserole in an airtight container and refrigerate for 1 to 2 days. Reheat individual portions in short increments in the microwave until hot; or cover with foil and reheat in a 350°F oven.
- Make-Ahead: Complete through step 4, cover and refrigerate. Mix the cracker crumb topping just before baking. Add a few extra minutes to the bake time since baking from chilled.
Nutrition
Pin for Later! New England Seafood Casserole
Easy and delicious! I substituted peas and carrots cot the mushrooms and used Marsala sherry and topped with puff pastry! Fabulous! A keeper, thanks for sharing!
Thanks for making! Love your swaps…like a seafood pot pie! Yum!
This was absolutely delicious, the money o spent on all the seafood was so worth it! I used a lb of sea scallops, same with shrimp, fish 1 lb, so I added a little more of all ingredients,
Thanks for sharing and I will too, Delicious
That’s so amazing to hear! #seafoodforever!
Absolutely delicious!
😍😍😍
Just made this pretty much as instructed, but I used tilapia instead of cod and I didn’t have sherry so I used sake. Was delicious, served it over rice with a side of stir-fried veggies. Thank you for the recipe.
Thanks for your comment! Sake, huh? I’m intrigued…and love how you adapted it!
Can this recipe be made in advance?
Hi Elaine! You can certainly assemble the entire casserole (through step 4), cover, and refrigerate. Add the crumb topping just before baking. It may require a couple extra minutes since it’s been in the fridge. Because it bakes quickly, I recommend baking it just before serving for best results.
Can you substitute Patagonia Scallops for the cod fish?
Absolutely! Depending on the size of all the seafood you are including, keep a close eye on the casserole and bake time so the seafood doesn’t overcook.
Hi, can I add lobster to your casserole? Could you serve over rice? What bread would you suggest?
Absolutely! This casserole is super customizable. If you want lobster, go for it (and, yum)! If using pre-cooked lobster, simply add it to the casserole like you would scallops or shrimp. For raw lobster, gently sauté it like you would cod, but just until it starts to turn pink (so as not to overcook it). Let me know how it goes!
I made this in advance through step 4 using haddock, shrimp and scallop medallions and used white wine since I didn’t have any sherry. I’ve never made a fish dish like this before. Covered tightly and baked the following day. Added green onions and cracker topping before baking. It took about a half hour at 400 degrees. It was really good. I made mashed potatoes on the side. Do you think it would be good with a mashed potato topping? I will make this again. I may try a puff pastry topping as another commenter suggested.
Fantastic make ahead tips, Amy! It makes sense that the bake time took a bit longer after being chilled, but so happy you enjoyed it. Topping the casserole with mashed potatoes will essentially give you a fisherman’s pie! You may need to adjust the bake time and/or temperature a bit, or give it a minute or so under the broiler at the end to give the potatoes a nice golden brown color.
Making it now
Moving south from Boston, I’ve made similar recipes. This one looks so easy and delicious and I will comment after I make it! Thank you for putting it out there!
– Pate
I followed the recipe exactly…loved it! Thanks!
I’ll also try it with haddock. Do you consider haddock to be a delicate fish that would not require pre-cooking?
Yay! Haddock is a great one to try. It’s a little more tender and generally smaller than cod, so it could go right in without precooking. It will really depend on the thickness/size of the fillet.
Ingredients says heavy cream but recipe says whisk half and half?
Gah! Heavy cream. Thanks for the catch (I can’t believe no one saw/mentioned that before)!
Tried to give this 5 stars, but the last star would not select. So 5 STARS
I used halibut, as I had one last wild caught small fillet. This was amazing and exactly what I’ve been searching for, but next time it’s gonna be lobster!!
Thank you so much for sharing.
I love this…thank you, Virginia! Yum…lobster!
Made this for a special birthday dinner and everyone loved it. Leftovers reheated gently the next day we’re still very good.
So happy to hear it! Hope you had a memorable celebration!
can this be made in advance and reheated
Hi Anne, You can assemble the entire casserole (through step 4), cover, and refrigerate. Add the crumb topping just before baking. It may require 5 to 10 extra minutes since it’s been in the fridge. Because it bakes quickly, I recommend baking it just before serving for best results.
only liquid is 1/2 cup of cream and 1/4 cup sherry. is that correct? thats very different from most seafood casseroles. i want to make it soon
Thank you for this great recipe. Everybody loved it. And thank you for your help Linda and responding so quickly in answering my questions. Much appreciated. I’m looking forwarding to trying more of your recipes.
Yay! Glad you all enjoyed it! Just curious…did you follow the liquids exactly or adjust up/down?
Has anyone tried real breadcrumbs vs Ritz?
Kris, it doesn’t appear so in the comments, but who knows?! I’d swap the Ritz for Panko…about 3/4 cup.
this looks great! can’t wait to try it for Christmas. would colossal shrimp (13/15 per pound) require pre-cooking? im assuming halibut should be pre-cooked like the cod? thank you.
Hi Adelle! Skip precooking the colossal shrimp…that 15-20 min in the oven at 400 should still do the trick…nothing worse than rubbery shrimp. You’re spot on with the halibut…do a quick sear like the cod. Since halibut is more ‘meaty’ (& may dry out faster than cod), check it with a thermometer or do a visual check that the halibut is cooked to your liking at that 15 min mark. Have a delish Christmas!
Can you make this ahead of and use half and half?
Ed, You can assemble the entire casserole (through step 4), cover, and refrigerate. Add the crumb topping just before baking (may need to add a couple extra minutes if baking from chilled). Half and half is fine to use; the sauce just won’t be as rich.
Can I use salmon instead of cod
You certainly can. Sauté just as you would the cod in step 2. Salmon will give it a more hearty spin, but I think it’ll be great with the sauce.