Baked Flounder
Delicate flounder fillets baked in a lemon-garlic butter until they turn snow-white and flake at the touch of a fork. Because flounder is so thin and lean, a hot 400°F oven and a short bake keep it moist while the butter, garlic, and paprika do the flavoring for you. It goes from fridge to table in about 25 minutes, making it a genuinely easy weeknight fish dinner.
Heat the oven to 400°F (200°C) and butter a 9x13-inch baking dish. Pat 4 skinless flounder fillets (about 6 oz / 170 g each) completely dry, season both sides with 1/2 teaspoon salt and 1/4 teaspoon pepper, and lay them in the dish, tucking any thin tail ends underneath. Stir together 4 tablespoons melted butter, 3 minced garlic cloves, 2 tablespoons lemon juice, 1 teaspoon lemon zest, and 1 teaspoon paprika, pour it evenly over the fish, and bake 10-12 minutes, until the flesh is opaque and flakes easily (130-140°F / 54-60°C internal). Rest 3 minutes, spoon the pan juices back over, and finish with chopped parsley and lemon slices.
- Pat the fillets truly dry before seasoning — surface moisture steams the fish and waters down the butter sauce.
- Flounder is thin and cooks fast: start checking at 10 minutes and pull it the moment it flakes or hits 130-140°F (54-60°C).
- Fold skinny tail ends under each fillet so everything is an even thickness and the edges don't overcook.
Equipment
- 9x13-inch (23x33 cm) baking dish
- Small saucepan or microwave-safe bowl
- Citrus zester or Microplane
- Instant-read thermometer
- Thin fish spatula
מצרכים
For the flounder
- 680 g skinless flounder fillets, 4 fillets about 6 oz each; thawed if frozen and patted very dry
- 3 g fine sea salt
- 0.5 g freshly ground black pepper
Lemon-garlic butter
- 56 g unsalted butter, melted, plus a little more for greasing the dish
- garlic cloves, finely minced
- 30 ml fresh lemon juice, from about 1 lemon
- 2 g lemon zest, finely grated
- 2 g sweet paprika
To finish
- 8 g fresh flat-leaf parsley, chopped
- lemon, sliced into rounds, for serving
אופן ההכנה
- שלב01
Set a rack in the middle of the oven and heat it to 400°F (200°C). Lightly butter a 9x13-inch (23x33 cm) baking dish so the delicate fillets release cleanly after baking.
- שלב02
Pat each fillet thoroughly dry on both sides with paper towels — this is the single biggest defense against watery, steamed-tasting fish. Season both sides evenly with the salt and pepper.
- שלב03
Melt the butter in a small saucepan over low heat or in short bursts in the microwave. Stir in the minced garlic, lemon juice, lemon zest, and paprika. The mixture will look loose and slightly separated; that is fine — it comes together over the fish in the oven.
- שלב04
Lay the fillets in the buttered dish in a single layer without overlapping, folding any paper-thin tail ends underneath so each piece is an even thickness. Pour the lemon-garlic butter evenly over the fish, using a spoon to coat any dry spots.
- שלב05
Bake for 10-12 minutes, until the flesh has turned from translucent to opaque white and flakes easily when nudged with a fork at the thickest point. An instant-read thermometer should register 130-140°F (54-60°C). Thin fillets under 1/2 inch may be done at the 10-minute mark, so check early.
- שלב06
Let the fish rest in the dish for 3 minutes so the juices settle, then spoon the buttery pan sauce back over each fillet. Scatter with parsley, add the lemon slices, and lift the fillets out with a thin fish spatula to serve.
Make ahead
The lemon-garlic butter can be mixed up to 2 days ahead and refrigerated; rewarm it until pourable before using. You can also pat dry, season, and arrange the fillets in the baking dish up to 4 hours ahead, covered in the fridge — but wait to add the butter until just before baking, since the lemon juice will start to "cook" the surface of the fish if it sits too long.
Storage
Refrigerate leftovers in an airtight container within 2 hours of baking and eat within 2 days. Reheat gently, covered, in a 275°F (135°C) oven for about 10 minutes with a spoonful of the pan juices or a splash of water — the microwave tends to toughen it and amplify fishy aromas. Freezing cooked flounder is not recommended; the thin, delicate flesh turns mushy when thawed.
Variations
Parmesan-crumb crust
Toss 1/2 cup (30 g) panko with 1/4 cup (25 g) grated Parmesan and 1 tablespoon melted butter, sprinkle it over the sauced fillets, and bake as directed, adding 1-2 minutes and a quick broil at the end for a golden top. Note this version adds gluten and more dairy; use gluten-free panko to keep it celiac-friendly.
Dairy-free Mediterranean
Swap the butter for 4 tablespoons (60 ml) extra-virgin olive oil and scatter 1 cup halved cherry tomatoes, 2 tablespoons capers, and a handful of sliced Kalamata olives around the fillets before baking. The tomatoes collapse into a bright, briny pan sauce and the dish becomes fully dairy-free.
Old Bay and lemon
Replace the paprika with 1 1/2 teaspoons Old Bay seasoning and cut the added salt to 1/4 teaspoon (Old Bay is salty). This gives the fish a Chesapeake-style flavor that is excellent with corn on the cob and coleslaw.
Serve with
Nutrition per serving
Nutrition values are estimates based on the metric measurements. Adjust as needed.
שאלות נפוצות
What does flounder fish taste like?
Flounder fish is one of the mildest, sweetest white fish you can buy — there is nothing 'fishy' about a fresh fillet. The flesh is thin, lean, and very delicate, with fine flakes closer to sole than to cod. That mildness is exactly why this recipe leans on lemon, garlic, butter, and paprika: the fish carries those flavors beautifully without being masked.
Can I use frozen flounder fillets?
Yes, and much of the flounder fish sold in the US is frozen at sea, so it is often the freshest option. Thaw the fillets overnight in the refrigerator (or sealed in a bag under cold running water for about 30 minutes), then pat them extremely dry before seasoning. Skipping the drying step is the main reason frozen fillets bake up watery.
How do I know when baked flounder is done?
Flounder is done when the flesh turns from translucent gray to opaque white and flakes easily when you press a fork into the thickest part. On a thermometer that is 130-140°F (54-60°C) at the center. Because the fillets are usually less than 1/2 inch thick, they can go from perfect to dry in a couple of minutes, so start checking at 10 minutes.
Can I substitute another fish in this recipe?
Any thin, mild white fish works with the same method: sole, tilapia, and small haddock or catfish fillets bake in roughly the same 10-12 minutes. Thicker fillets like cod or halibut also taste great with the lemon-garlic butter but need 14-18 minutes depending on thickness, so cook to temperature rather than time.
Why did my flounder come out mushy or watery?
Three usual culprits: the fillets were not patted dry, they were thawed too quickly (or refrozen at some point), or they were overbaked so the flesh wept liquid into the dish. Buy flounder fish that smells clean like the ocean, dry it aggressively with paper towels, and pull it from the oven the moment it flakes — the 3-minute rest finishes the cooking gently.
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