20-Minute Baked Flounder recipe
This baked flounder recipe is the perfect weeknight meal. It’s easy, wholesome, and ready in just 20 minutes!
New to Fish? Start With a Baked Flounder Recipe.
Whether you’re new to eating fish or cooking it—or both—this baked flounder au gratin is the perfect starting point. Flounder is a very mild white fish with a flaky texture and a clean flavor; it’s not fishy at all! And the crispy topping adds a pop of extra flavor with thyme and parmesan, making it easy for newbies to enjoy. Easy to prep and cook, this flounder takes about 20 minutes to bring together and pairs with most veg and starch sides. So, if you’re looking to incorporate more fish into your diet, this is a fantastic starting point.
For more useful info, check out my Fish & Seafood Guide.
Ingredients to Add to Your Shopping List.
- Flounder fillets
- Olive oil
- Panko breadcrumbs
- Parmigiano Reggiano cheese
- Sea salt
- Cracked black pepper
- Fresh parsley
- Lemon wedges
How to Bake Flounder.
Baking fish can be nerve wracking because it overcooks so easily, and once fish is overcooked, it’s impossible to enjoy. Flounder fillets aren’t thick like salmon or sea bass, so you want to keep a close on eye on it if you’re new at cooking fish. Here’s how to make this baked flounder recipe:
Preheat the oven to 400° F.
Put the flounder onto a parchment-covered sheet pan or lightly oiled baking dish and gently blot them with a paper towel to absorb excess moisture.
Let the fillets come to room temperature—this should take about 15 minutes. This will help you get a more even cook.
Hit the fillets with a sprinkle of salt and pepper, then brush the tops of the fillets with olive oil.
Combine the panko breadcrumbs, grated cheese, a pinch of salt, and dried thyme in a small mixing bowl. Then add the rest of the olive oil to the crumb mixture, and mix it with a fork until the crumb mixture becomes buttery, crumbly, and golden.
Sprinkle the crumb mixture over the fillets and lightly press the crumbs down onto the fillets.
Bake the fish for 10-12 minutes. The fish should be opaque, flake easily with a fork, and have an internal temperature of 145° F.
Finish the fillets off with some freshly chopped parsley and serve with lemon wedges for spritzing.
Useful Tools for This Recipe:
- Sheet pan
- Parchment paper
- Sharp knife
- Cutting board
- Mixing bowl
- Measuring cups and spoons
- Cheese grater
Recipe tips + tricks.
- For a little extra indulgence, use melted butter instead of olive oil.
- This recipe works with any white fish fillets, though cooking time will vary. Thicker fillets will take a bit longer.
- Italian breadcrumbs will work in place of panko.
Have You Made This Recipe?
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Sides to Serve With This Baked Flounder Recipe:
- Herb and Garlic Instant Pot Mashed Potatoes
- Easy Dinner Side Salad with Lemon Juice
- Baked Crispy Smashed Potatoes with Garlic and Rosemary
- Beer Butter Mushrooms
- Best Oven-Roasted Broccoli with Nutritional Yeast
Get the Recipe:
20-Minute Baked Flounder au Gratin
- 4 6 oz flounder fillets, No flounder? You could use any white fish for this recipe.
- 2 TBSP extra virgin olive oil, divided
- 1 cup panko breadcrumbs
- 2/3 cups freshly grated Parmigiano Reggiano cheese
- 1/2 tsp kosher salt
- A few grinds of cracked black pepper
- 1 tsp dried thyme, You could also use a dried Italian herb mix
- Chopped fresh parsley, for garnish
- Lemon wedges, for serving
- Preheat the oven to 400° F.
- Place the flounder fillets on a parchment-covered sheet pan or lightly oiled baking dish. Lightly blot them with a paper towel to absorb excess moisture and let the fillets come to room temperature by leaving them out for about 15 minutes before placing them in the oven. (This will help you get a more even cook.) Season the fillets with a sprinkle of salt and pepper, then brush the tops of the fillets with 1 TBSP of the olive oil.
- In a small bowl, combine the panko breadcrumbs, grated cheese, a pinch of salt, and dried thyme. Add the rest of the olive oil to the crumb mixture and mix with a fork until the crumb mixture becomes buttery, crumbly, and golden in color.
- Sprinkle the crumb mixture over the fillets and lightly press the crumb mixture down into the fillets.
- Bake the fish for 10-12 minutes, or until the fish is opaque, flakes easily with a fork, and reaches an internal temperature of 145° F.
- Garnish with freshly chopped parsley and serve with lemon wedges for spritzing.
46 Comments on “20-Minute Baked Flounder recipe”
I made this last evening and it was amazing! I put some pesto on the flounder before adding the crumb mixture and what a winner! My hubby kept telling me how good it was and it made my day! Thank you for a great recipe that we will use often!
Ruth! This makes me so happy. Adding pesto sounds perfect :)
I love the crunchy cheesy topping that added so much flavor to this baked seafood dish!
Oh yum! I love how easily this flounder comes together for those new to working with fish. It looks fantastic, especially with that crust!
This flounder recipe is fantastic! So flavorful and easy to make, so good!
Love how healthy this recipe is, and the panko gave it great texture!
I love a good fish recipe that’s easy to make! So great for my meal preps to make for lunch!
Best baked fish recipe I’ve yet to find! Thank you!
This recipe has become a white fish staple in this house. Whether I’m using halibut, cod, flounder, whatever. Might try it with salmon too. The crumb topping is so delicious.
Love it! Let me know how it is with salmon :)
What a perfect baked fish recipe! Love that you used flounder too. Will try with cod next time I make it.
Let me know how it goes with cod! I’ve done it with halibut before and it was great. Works so well with any fish!
This sounds like a perfect weeknight dinner to me! I love baking fish as quick meals all the time, thanks for posting this!
Big fan of flounder. This Parmesan, Reggiano, Panko breaded sounds amazing! Can’t wait to try it.
Breading is always a hit ;)
I love how fast and easy this recipe is! This delicious flounder recipe is definitely going into my dinner rotation!
This was so good! And so easy to make! My kids loved it and it’s usually impossible to get them to eat fish. Thanks so much!
I love that, Genevieve! Now if only I could get my toddler to eat it… :x
I made this with Cod and it was so so flavorful and EASYYYY!!! Perfect weeknight meal–thank you!
I’m so glad you enjoyed it!
My kids love a breaded fish and we all loved this one. Thanks for the great recipe!
I’ve never grown out of my love for breaded fish even as an adult, haha. Glad it was a hit!
This was everything a gourmet meal should be, and then some! Turned out perfectly tender and juicy; worthy of a restaurant, indeed!
Thanks so much! It’s definitely one of those recipes that surprises you: simple but elegant!
I love that this recipe only takes 20 minutes! It is on our dinner menu for this week!
Right? The faster, the better, haha.
Love that crispy panko coating on the fish, it’s so delicious!
I’m so glad :)
I eat fish a few times a week, so I’m excited to try this easy flounder recipe. Sounds delicious :)
Keep me posted!
This is a nice change to just a pan fried version I love that its baked and au gratin great flavors!
I’m glad you enjoy it, Claudia!
You had me at au gratin! So good!
Au gratin is hard to resist ;)
I can’t believe this is only 20 minutes. Such a perfect midweek dinner recipe!
Glad you’re enjoying it!
This is such a perfect combination of flavours and textures. Everyone absolutely loved it! Thank you for a great recipe.
I’m so happy to hear this!
This baked flounder is so flaky and the cheese and breadcrumb topping is delicious. Such a great meal when you’re short of time.
This makes me so happy!
I tried the Baked Flounder Au Gratin recipe and my entire family loved it! This will be enjoyed again very soon.
I’m SO thrilled to hear this! I keep meaning to make this recipe again myself. The bummer about blogging about food is that I always feel pressure to make new things — thanks for reminding me that I need to make time to revisit some oldies :) And thanks so much for taking the time to stop by with feedback!
So I actually never made the connection until now that flounder is a real actual fish. I would like to blame Disney and The Little Mermaid but I think my child brain probably thought I would never eat a character in a Disney movie. Child brain was so wrong, because this looks fantastic!
It definitely isn’t spoken of TOO often, so don’t feel too bad ;)
Just go into adult brain mode while making and eating this, and then go back to child brain mode. (Always go back to child brain mode!)