Name: Crab Stuffed Flounder Recipe with Lemon Caper Sauce
Prep time: 10 min
Cook time: 30 min
Total time: 60 min
Ingredients: 1 large egg; 2 tablespoon mayonnaise; 1 tablespoon Italian parsley (finely chopped); 1 teaspoon Old Bay seasoning (plus more to sprinkle over the fish); ½ teaspoon lemon zest; 8 ounce lump crab meat (slightly broken apart); ¼ cup red bell pepper (finely diced (or any color bell pepper)); 2 green onions (chopped); 10 Ritz crackers (crushed, just shy of ½ cup (or bread crumbs / crushed saltines)); 1½ pounds flounder fillets ((four ~6 oz fillets)); 2 tablespoon unsalted butter (melted); ¾ cup low sodium chicken broth ((or vegetable broth, seafood stock, white wine)); 2 tablespoon lemon juice (from one lemon); 1 tablespoon shallot (minced); 2 tablespoon capers (rinsed); 3 tablespoon unsalted butter (cut into 6 pieces, chilled); 1 tablespoon Italian parsley (finely chopped)

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This Crab Stuffed Flounder Recipe with Lemon Caper Sauce is a simple yet special dish perfect for celebrations or cozy family dinners. Rich crab, tender flounder and a bright sauce create a delightful burst of flavors!

A fork spearing a crab stuffed flounder roulade on a bed of arugula.

Why and When to Make This Recipe

If you’re after a dish that’s fancy enough for celebrations but also perfect for cozy family dinners, you’re in for a treat!

Rich crab meat meets a flaky, simple flounder fillet, and is complimented by a bright, citrusy sauce. The mix of flavors will make your taste buds really happy. Prepare and assemble the stuffed flounder in just about 30 minutes. While it bakes, make the lemon caper sauce and toss a simple fresh salad to have a stunning meal in about an hour.

Enjoy this recipe anytime you’re craving a seafood dinner. It’s a delicious meal perfect for family dinners or small get-togethers, whether you’re celebrating the end of a week, toasting a special occasion with friends, or transforming an average evening into an impromptu date night!

Raw ingredients for stuffed flounder arranged on a marble table.

Gather Your Ingredients

I’ve provided substitutions next to the key ingredient to help you tailor this recipe to your needs or personal taste.

Flounder fillets – flounder is a mild, white fish. It’s texture is delicate and becomes flaky when cooked. Fillets will vary in size and thickness at the grocer; look for fillets that are roughly 6 oz each or purchase fish fillets that are as similar in size as possible. Good substitutes are sole or halibut (though halibut tends to be thicker and more expensive).
Lump crab meat – lump meat is white and comes from the body of the crab. It will have a mix of large lumps and smaller pieces. I recommend purchasing fresh crab from the seafood counter for the best quality and flavor (as opposed to shelf-stable canned crab).
Red bell pepper – the sweet crunch and vibrant color red bell pepper is a great compliment to the rich flavor and tender texture of the seafood. Swap red for yellow, orange or even green bell pepper.
Green onions – these provide a mild onion flavor to the crab stuffing.
Ritz crackers – one of the binders for our filling and a great way to add a layer of buttery flavor. You can substitute with seasoned bread crumbs or saltine crackers instead.
Large egg – another binder, to help keep the crab stuffing stuffed inside the fillets as it bakes.
Mayonnaise – not too much, but enough to lend its tangy flavor.
Fresh parsley – I prefer flat leaf parsley, but you can certainly use the curly variety. It goes into the stuffing and the sauce.
Fresh lemon juice + zest – one lemon can provide the zest for the stuffing and juice for sauce.
Old Bay seasoning – the quintessential Mid-Atlantic seafood seasoning that’s packed with flavor.
Unsalted butter – you’ll use butter in two ways: melted butter is drizzled over the fish before baking to keep it tender and moist throughout baking; chilled butter is whisked into the sauce to create rich, velvety texture.
Low sodium chicken broth – broth is the base for the sauce, adding flavor and tempering the acidity of the lemon juice. You can swap chicken broth for vegetable broth, seafood stock or white wine.
Shallot – just a little of this allium helps flavor and scent the sauce. You can omit the shallot if you like.
Capers – these unripened flower buds pack a punch. You’ll typically find them jarred in brine, but are also available packed in salt. They are excellent with seafood. Give them a good rinse to get rid of the extra salt.

A flounder fillet stuffed with crab meat on a bed of arugula topped with a lemon slice.

Let’s Get Cooking

Here’s a step-by-step guide to help you on your way to making this delish stuffed flounder recipe.

Mix the crab stuffing – In a mixing bowl, whisk together the egg, mayonnaise, parsley, lemon zest, and Old Bay. Add the crab meat, bell pepper, green onions and crushed crackers; fold to combine.
Stuff the flounder fillets – Lay the flounder fillets on a clean work surface (nicest looking side facing down). Divide the crabmeat stuffing between the fillets and spread across the top of the fish. Starting at the tail end, roll up each fillet and place in a baking dish spritzed with cooking spray, seam side down. Brush or drizzle with melted butter, then season the tops with additional Old Bay. Bake for 25-30 min in a 350°F preheated oven. (The cooking time will vary based on the size and thickness of the fillets.)
Make the lemon caper sauce – In a small saucepan, combine chicken broth, lemon juice and shallot. Bring it to a boil over medium-high, then reduce to medium heat and simmer for about 7 minutes. Stir in the capers, then take it off the burner. Whisk in the chilled butter, once piece at a time, until the sauce has thickened. Stir in the parsley. Taste and season with kosher salt and black pepper to taste.
Serve – Spoon the sauce over the stuffed flounder and serve.

Lump crab, green onions, red bell peppers in a mixing bowl with sauce.

A flounder fillet covered with crab meat stuffing on a sheet of parchment paper.

Tips for Choosing + Handling Fresh Seafood

Make the most of your investment with these tips…

Ask the fishmonger! – I’ll ask the folks at the seafood counter when the catch came in, if they have an opinion about it, and if something isn’t available, can they recommend a substitute.

Can I smell that? – Ask to smell before you buy, too…there should be no smell or a briny ocean smell. If you get a whiff of ammonia, move on.

What to look for with whole fish – If you’re feeling ambitious and purchase a whole flounder to fillet at home, make sure the whole fish is packed on ice at the seafood counter or shop. Look for clear eyes, bright gills and firm flesh.

What to look for when buying fillets – With fillets, the flesh should be translucent and moist.

Once you get your fish home – When you bring fresh flounder fillets home, fill a baking sheet or pan with a layer of ice. Cover the ice with a sheet of parchment paper, and set the fillets on top. Cover and store in the fridge if you’re not cooking right away.

Using frozen fish – When good fresh fish isn’t available, and you can plan ahead, purchase frozen. Remove the frozen fillets from their packaging. Line a baking sheet with a tea towel or a couple layers of paper towel and arrange the fish in a single layer. Cover tightly and refrigerate overnight. The towels will wick away excess moisture.

Storing and Reheating

How to store crab stuffed flounder – Immediately transfer leftover stuffed flounder to an airtight container and refrigerate. Store the sauce in a separate container. Enjoy leftovers within two days.

How to reheat stuffed flounder – To reheat, place in a greased baking dish and cover with foil to retain moisture. Bake at 350°F until it is heated through.

A crab stuffed flounder roulade with a bite missing next to a fork.

What to Serve with Stuffed Flounder

Crab stuffed flounder is sweet and delicate. Side dishes with simple, delicate flavors will really let your main course shine. Vegetable dishes like French green beans, creamed spinach, roasted broccolini or a simple green salad are perfect. For starchy sides, think herbed rice pilaf, roasted potatoes (with a milder herb like thyme or parsley), or a simple creamy orzo.

When it comes to a wine pairing, enjoy this recipe with an unoaked or lightly oaked Chardonnay, or a Chardonnay blend.

More Recipes for the Seafood Lover

Crab Stuffed Flounder Recipe with Lemon Caper Sauce

Linda Feller

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Main Course

American

413 kcal

Equipment

Ingredients

Crab Stuffed Flounder

1 large egg
2 tablespoon mayonnaise
1 tablespoon Italian parsley, finely chopped
1 teaspoon Old Bay seasoning, plus more to sprinkle over the fish
½ teaspoon lemon zest
8 ounce lump crab meat, slightly broken apart
¼ cup red bell pepper, finely diced (or any color bell pepper)
2 green onions, chopped
10 Ritz crackers, crushed, just shy of ½ cup (or bread crumbs / crushed saltines)
1½ pounds flounder fillets, (four ~6 oz fillets)
2 tablespoon unsalted butter, melted

Lemon Caper Sauce

¾ cup low sodium chicken broth, (or vegetable broth, seafood stock, white wine)
2 tablespoon lemon juice, from one lemon
1 tablespoon shallot, minced
2 tablespoon capers, rinsed
3 tablespoon unsalted butter, cut into 6 pieces, chilled
1 tablespoon Italian parsley, finely chopped

Instructions

Preheat oven to 350°F. Grease the bottom of a 9×13-inch baking dish with cooking spray.
In a medium bowl, whisk together the egg, mayonnaise, parsley, lemon zest, and Old Bay. Add the crab meat, bell pepper, green onions and crushed crackers; fold to combine.
Lay the flounder fillets on a clean work surface (nicest looking side facing down). Divide the crab mixture between the fillets. Starting at the tail end, roll up each fillet and place in the prepared baking dish, seam side down. Brush or drizzle with melted butter, then season the tops with additional Old Bay. Bake for 25-30 min.
While the fish bakes, make the sauce. In a small saucepan, combine chicken broth, lemon juice and shallot. Bring it to a boil over medium-high, then reduce to medium and simmer for about 7 minutes. Stir in the capers, then take it off the burner. Whisk in the chilled butter, once piece at a time, until the sauce has thickened. Stir in the parsley. Taste and season with kosher salt and black pepper to taste.
Spoon the sauce over the stuffed flounder and serve.

Notes

Tips for Choosing + Handling Fresh Seafood:

Seafood should have no smell or a briny ocean smell. If you get a whiff of ammonia, move on.
For whole flounder, make sure the whole fish is packed on ice at the seafood counter or shop. Look for clear eyes, bright gills and firm flesh.
For fillets, the flesh should be translucent and moist.
When you purchase fresh fillets the day you cook, fill a baking sheet or pan with a layer of ice. Cover the ice with a sheet of parchment paper, and set the fillets on top. Cover and store in the fridge if you’re not cooking right away.
Frozen fish is a great alternative when fresh isn’t available, but plan ahead. Remove frozen fillets from their packaging. Line a baking sheet with a tea towel or a couple layers paper towel and arrange the fish in a single layer. Cover tightly and refrigerate overnight. The towels will wick away excess moisture.

Storing and Reheating:

Immediately transfer leftovers to an airtight container and refrigerate. Store the sauce in a separate container. Enjoy leftovers within two days.
To reheat, place in a greased baking dish and cover with foil to retain moisture. Bake at 350°F until heated through.