Baked Flounder Recipe with Lemon Butter Sauce
Updated May 14, 2025, Published Jun 05, 2023
This post may contain affiliate links. Please read our disclosure policy.
This Baked Flounder Recipe with Lemon Butter Sauce is your new favorite weeknight fish recipe. It’s easy to make with minimal mess to clean and is super flavorful! The flounder is mild with a delicate texture and pairs well with the tangy and savory flavors of the lemon and garlic butter sauce. Enjoy this 20-minute meal!
See the complete list of What to Serve with Flounder for serving ideas.
Why This Recipe Stands Out
The buttery sauce keeps the fish tender while the lemon and garlic add bright, savory flavors. A touch of breadcrumbs takes it over the top and gives it that perfect golden finish—simple, satisfying, and so delicious! Even picky eaters will love fish this way.
” Awesome and easy! My non-fish-loving husband was very happy!”
– Cindy
Try my panko-crusted cod and fish en papillote (fish in parchment paper) next.
Table of Contents
Simple Ingredients
Flounder Fillets
- Flounder fillets or sole fish – Both are delicate, mild white fish with a tender texture. They bake quickly and absorb the lemon butter garlic flavors beautifully without overpowering them. Sole is slightly thinner and even more delicate, so it’s perfect if you want something extra light.
- Extra Virgin Olive Oil – Adds richness and helps keep the fish moist while baking.
- Kosher salt and freshly ground black pepper are used to taste.
Sauce
- Garlic cloves – Fresh garlic infuses the sauce with warm, aromatic depth and enhances the savory notes of the flounder.
- Fresh lemon juice – Bright and tangy, lemon juice cuts through the richness of the butter and balances the flavors.
- Lemon zest – Adds concentrated citrus aroma and a burst of fresh lemon flavor without extra acidity.
- Melted butter – Creates a luxurious, silky sauce that coats the fish and helps carry all the flavors into each bite.
- Coarse fresh breadcrumbs – Toast up to a crisp golden topping; they add just the right amount of crunch for texture contrast.
- Fresh parsley – Classic and mild, it brings color and freshness. For a twist, try:
- Lemon wedges, for serving – A finishing touch that lets everyone add a fresh squeeze at the table, brightening each bite.
See the recipe card for quantities.
Substitutions and Variations
- Herbs: Toss in fresh basil, tarragon, dill, rosemary, or thyme for extra flavor. Use homemade Italian seasoning.
- Spice It Up: A pinch of red pepper flakes adds a gentle kick. You’ll love my blackened cod recipe.
- Try New Citrus: Swap lemon for lime or orange for a fresh twist.
- Wine: A splash of white wine deepens the sauce’s flavor.
- Flavored Butter: Use garlic, or truffle butter for a richer taste. Try my creamy black truffle pasta recipe.
- Cheese: Sprinkle Parmesan over the breadcrumbs for a savory boost.
- Swap the Fish: Try cod, tilapia, haddock, or sole if flounder isn’t available.
How to Make Baked Flounder With Lemon Butter Sauce
This is a step-by-step photo overview of how to make baked flounder; the full instrcutions are in the recipe card below.
Step #1: Preheat oven to 350 degrees F. Lightly pat the fish with paper towels to remove excess moisture. Grease a shallow baking dish, cast-iron skillet, or baking sheet with a bit of butter. After the fish is patted dry place the fillets in the baking dish in an even layer and rub with olive oil, and season with salt and pepper. Cover and let rest for 30 minutes.
Step #2: Combine garlic, lemon juice, zest, and butter in a small bowl.
Step #3: Stir to combine.
Step #4: Pour the lemon-butter mixture over the fish.
Step #5: Sprinkle the flounder fish with bread crumbs.
Step #6: Bake for 15-25 minutes or until the fish is cooked and the topping is golden. Cooking time varies slightly depending on the thickness of the fillets. Bake until the fish is cooked through and flakes with a fork.
Storage & Reheating Instructions
Let the fish cool, then store it with the sauce in an airtight container in the fridge for up to 3 days. Reheat in a 350°F oven for 10–15 minutes, or gently in the microwave (though it may turn rubbery). For best quality, enjoy within 1–2 days and refrigerate promptly.
My Pro Tip
Recipe Tips
- Flounder fillets can be tough in texture and dry if overcooked. If you buy thin fillets, check for doneness after 10 to 15 minutes.
- Thicker cuts of fish may take longer than 25 minutes to cook through. Check the fillets starting at 20 minutes, even if they are thick, to prevent overcooking.
FAQ’s
The baking time for flounder fillets will depend on the thickness of the fillets. Generally, bake them in a preheated oven at 350°F (190°C) for 12-15 minutes for fillets that are 1/2 inch thick or 15-18 minutes for fillets that are 1 inch thick.
The best way to determine if the flounder is done baking is to use a meat thermometer. The internal temperature should reach 145°F (63°C). Another way to tell is to check if the flesh is opaque and flakes easily with a fork.
You don’t need to cover the baking dish when baking flounder fillets, especially when cooking in a butter sauce. However, if you want to keep the fish even more moist, you can cover it with foil during the first half of the cooking time.
Yes, you can bake frozen flounder fillets, but they will take longer to cook. Add 5-7 minutes to the baking time for frozen fillets. It’s also recommended to thaw the fillets in the refrigerator before baking to ensure even cooking.
Flounder is a mild white saltwater fish that is delicious when baked or fried. It has a nice flaky texture when baked this way. Flounder is a flatfish that is low in mercury, making it safe for pregnant women and kids of all ages to enjoy.
For this recipe, you do not have to flip the fish during the cooking time, but make sure to check it at the 15-minute mark to make sure it’s not overcooked.
Season flounder fillets with salt and pepper, then top with a lemon butter garlic sauce and a light sprinkle of breadcrumbs. It keeps the fish tender, flavorful, and perfectly golden!
More Fish Recipes
You will also love these fish recipes- Baked Cod, Sea Bass, Salmon Picatta, Baked Stuffed Flounder, Lemon Butter Cod, Easy Fish en Papillote Recipe, and Stuffed Salmon. You can also try my how long to bake chicken breast at 425 if you’re feeling more like chicken tonight instead of fish!
What to Serve with Baked Flounder
Serve this yellowtail flounder with potatoes or rice and an orange fennel salad or steamed asparagus.
More of my favorite side dishes to serve with this easy-baked flounder recipe with lemon butter sauce:
💙 MADE THIS RECIPE AND LOVED IT? 💙 Please leave a ⭐️STAR rating and COMMENT below- I love connecting with you! Tag me with your creations on Instagram and find me on Pinterest.
Baked Flounder Recipe
Ingredients
Fish Fillets
- 4 flounder fillets, or sole fish (2 pounds total)
- 1 tablespoon olive oil
- Kosher salt
- Freshly ground black pepper
Sauce
- 2 medium cloves garlic, minced
- 2 tablespoons fresh lemon juice
- Zest of 1 lemon
- 5 tablespoons unsalted butter, melted
- ⅓ cup coarse fresh breadcrumbs
- 1 tablespoon fresh chopped parsley, finely chopped, for serving (try tarragon for another fresh flavor option)
- 4 slices or wedges of lemon, for serving
Instructions
- Preheat oven to 350 degrees F. Lightly pat the fish with paper towels to remove excess moisture. Grease a shallow baking dish, cast-iron skillet, or baking sheet with a bit of butter. Place the flounder fish fillets in the baking dish in an even layer and rub with olive oil, and season with salt and pepper. Cover and let rest for 30 minutes.
- Combine garlic, lemon juice, zest, and butter in a small bowl. Stir to combine. Pour the lemon-butter mixture over the fish. Sprinkle the flounder fish with bread crumbs.
- Bake for 15-25 minutes or until the fish is cooked and the topping is golden. Cooking time varies slightly depending on the thickness of the fillets. Bake until the fish is cooked through and flakes with a fork.
- Let stand for 5 minutes before serving. Sprinkle with parsley (or tarragon) and serve with fresh lemon wedges. After plating the fish- spoon sauce from the baking dish on top of the fish. Enjoy! Serve with potatoes, or rice, and a simple salad and vegetables.
Notes
- Flounder fillets can be tough in texture and dry if overcooked. If you buy thin fillets, check for doneness after 10 to 15 minutes.
- Thicker cuts of fish may take longer than 25 minutes to cook through. Check the fillets starting at 20 minutes, even if they are thick, to prevent overcooking.
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
Awesome and easy! My non-fish-loving husband was very happy!
Yay! So happy he loved this easy and tasty recipe!
This was an amazing recipe. I made it tonight and my husband loved it 😊
Yay! We love it, too, for its simple and fresh taste.
I made this today and loved it! It’s only my second time cooking flounder, and I loved the addition of the breadcrumbs especially. Thank you!
Yes! The breadcrumbs add a special touch!
My favorite way to enjoy white fish! I use Tilapia for this recipe too.
I used talapia with the garlic butter sauce fish recipe. The recipe was super easy to make & so delicious!
Our side dish was roasted red potatoes & broccoli, Italian tomatoes salad with garlic toast.
Thank you, Elena!
Yes! I’ve made with tilapia and it is equally yummy. Happy you loved it.