Creamy Dijon Seafood Casserole: A Coastal Comfort Dish 2025
Few dishes capture the essence of coastal cuisine like a well-made baked seafood casserole. With tender flounder, succulent shrimp, sweet scallops, and rich lump crabmeat enveloped in a luxurious cream sauce, this dish is perfect for entertaining or a comforting night in. Beyond its elegant appearance, this casserole balances flavors and textures beautifully, creating a meal that feels gourmet yet is surprisingly easy to prepare.
Whether you are a seafood aficionado or a home cook looking to impress, this complete guide will walk you through every step—from choosing the best seafood to achieving the perfect golden finish.
Why This Baked Seafood Casserole Stands Out
There are countless seafood recipes, but this casserole offers unique qualities that make it unforgettable:
- Elegant but approachable: It looks like a restaurant-quality dish but is simple enough for home cooking.
- Versatile seafood combination: Flounder, shrimp, scallops, and crab are just a starting point—you can customize to taste.
- Perfect for any occasion: Holidays, dinner parties, or a special weekday dinner.
- Balanced flavors: The creamy Dijon sauce enhances the seafood without overpowering it.
- Easy adjustments: Swap seafood, add vegetables, or make it gluten-free as needed.
Ingredients You’ll Need
To make the perfect baked seafood casserole, start with high-quality ingredients. Here’s a breakdown:
Seafood
- Flounder fillets – mild, flaky, and tender, forming the casserole’s base.
- Shrimp – peeled and deveined; sear for juicy, sweet bites.
- Scallops – bring a buttery, delicate texture.
- Lump crabmeat – adds richness and a slightly sweet, decadent flavor.
Cream Sauce
- Butter & flour (beurre manié) – thickens the sauce smoothly without clumps.
- Heavy cream & chicken stock – provide a creamy base that lets seafood shine.
- Dijon mustard – adds subtle tang and depth.
- White wine – brightens flavors and enhances the sauce.
- Old Bay seasoning – classic coastal spice.
- Fresh herbs (parsley, thyme) – elevate the dish with freshness.
Optional Toppings
- Grated parmesan – for a golden, cheesy crust.
- Breadcrumbs – add a satisfying crunch.
Pro Tips Before You Begin
- Use fresh or properly thawed seafood – ensures the best texture and flavor.
- Avoid overcooking – shrimp and scallops cook quickly and finish in the oven.
- Master the beurre manié – combine butter and flour in equal parts to prevent lumps in the sauce.
- Customize your seafood – don’t hesitate to swap flounder for cod, sole, or tilapia.
- Prep ahead – the casserole can be assembled and refrigerated, then baked just before serving.
Step-by-Step Instructions: How to Make Baked Seafood Casserole
Step 1: Prepare and Sear the Seafood
- Pat the shrimp and scallops dry to remove excess moisture.
- Heat butter in a large skillet over medium-high heat.
- Add shrimp and scallops, searing for 1–2 minutes per side until lightly golden.
- Deglaze the pan with white wine, scraping up any flavorful bits.
- Add heavy cream, chicken stock, Dijon mustard, Old Bay seasoning, and fresh herbs.
- Simmer for 1–2 minutes, then remove the seafood and set aside.
Tip: Keep the sauce on low heat to prevent curdling.
Step 2: Thicken the Cream Sauce
- Prepare beurre manié: mix equal parts butter and flour until smooth.
- Gradually whisk the beurre manié into the cream sauce.
- Stir continuously over medium heat until the sauce reaches a velvety consistency.
- Gently fold in the seared shrimp, scallops, and lump crabmeat.
- Set the finished mixture aside for assembly.
Step 3: Pre-Bake the Flounder
- Preheat your oven to 350°F (175°C).
- Place flounder fillets in a lightly greased casserole dish with a small splash of water.
- Sprinkle with Old Bay seasoning for a subtle coastal flavor.
- Bake for 10 minutes, then drain excess liquid.
Tip: Pre-baking the fish prevents a watery casserole and ensures even cooking.
Step 4: Assemble and Bake
- Spoon the creamy seafood mixture over the baked flounder evenly.
- Optional: sprinkle with breadcrumbs or grated parmesan for a golden top.
- Bake at 350°F (175°C) for 25–30 minutes, until bubbly and lightly golden.
- Let the casserole rest for a few minutes before serving.
Step 5: Garnish and Serve
- Top with fresh chopped parsley for color and freshness.
- Serve warm alongside:
- Buttery mashed potatoes or rice pilaf
- Crisp green salad with lemon vinaigrette
- Garlic bread or a crusty French loaf
Variations to Elevate Your Casserole
- Different seafood: cod, tilapia, or even lobster chunks.
- Cheesy twist: add a layer of mozzarella or gruyère.
- Vegetable boost: stir in peas, spinach, or diced bell peppers.
- Spicy option: add a pinch of cayenne, paprika, or hot sauce to the sauce.
- Gluten-free: use gluten-free flour for the beurre manié.
Storage & Leftovers
- Store in an airtight container in the fridge for up to 2 days.
- Reheat gently in the oven to prevent separating the cream sauce.
- Freezing is not recommended due to cream sauce texture.
Frequently Asked Questions
Can I make this casserole ahead of time?
Yes, assemble and refrigerate. Bake just before serving to maintain texture.
Can I use frozen seafood?
Absolutely! Thaw completely and pat dry to avoid excess water.
What if I don’t have flounder?
Swap with any mild white fish, such as cod, tilapia, or sole.
Is this dish gluten-free?
Not as written—substitute flour in beurre manié with a gluten-free alternative.
Can I use half-and-half instead of cream?
Yes, but expect a slightly thinner and less rich sauce.
What’s the purpose of beurre manié?
It thickens the sauce smoothly without lumps, giving the sauce a silky texture.
Can I use pre-cooked shrimp or crab?
Yes. Stir in at the end to heat through without overcooking.
Tips for Perfect Seafood Texture
- Do not overcrowd the skillet when searing—this ensures a golden crust.
- Pat seafood dry before cooking to prevent sogginess.
- Use a gentle folding motion when mixing seafood into the sauce to avoid breaking delicate pieces.
Enhancing Flavor
- Add lemon zest or a squeeze of lemon juice for brightness.
- Fresh herbs like tarragon, dill, or chives can provide unique coastal notes.
- A drizzle of extra virgin olive oil before serving can enhance richness.
Why This Recipe Works for Any Occasion
- Dinner parties: looks impressive and can be partially prepared ahead.
- Weeknight dinners: easy to assemble and bake.
- Special holidays: elegant enough for a celebratory table.
- Family meals: versatile to suit picky eaters with different seafood or toppings.
Sensory Experience
From the moment the casserole comes out of the oven, the aroma of butter, Dijon, and fresh seafood fills the kitchen. The first bite offers a silky, creamy sauce, followed by succulent shrimp and scallops, with flounder providing a delicate foundation. Each mouthful is a harmonious balance of richness, freshness, and subtle spice that will have everyone reaching for seconds.
Optional Pairings
- White wine: Chardonnay or Sauvignon Blanc complements the creamy sauce.
- Side dishes: Roasted asparagus, lemony green beans, or a crisp arugula salad.
- Bread options: Rustic baguette or garlic knots for soaking up sauce.
Final Thoughts
This baked seafood casserole is a celebration of flavors and textures, from the delicate flounder to the decadent cream sauce enriched with Dijon and wine. It combines sophistication and comfort in one dish, making it a must-try recipe for seafood lovers and home chefs alike. With clear steps, helpful tips, and versatile variations, it’s a recipe that will become a staple in your cooking repertoire.
Whether you’re impressing guests or treating yourself, this casserole proves that elegant cooking doesn’t have to be complicated. Every bite delivers coastal charm, creamy indulgence, and a hint of gourmet flair, making it impossible to resist.
