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This baked flounder recipe is a great way to get your family to eat more fish. Flounder is mild in flavor, and the cheesy breadcrumb topping adds a nice touch of texture and flavor. It’s incredibly easy and it’s ready in 20 minutes, which makes it a weeknight option.
Table of Contents
- Why You’ll Love This Recipe
- Ingredients for Baked Flounder Au Gratin
- Recipe Variations & Modifications
- How to Make Baked Flounder Au Gratin
- Recipe Tip
- How to Serve Baked Flounder Au Gratin
- Storage & Reheating
- Frequently Asked Questions
- More Easy Fish Recipes for Your Weeknights…
- 20-Minute Baked Flounder au Gratin Recipe
If you’re new to cooking fish, or eating it, this baked flounder is the perfect starting point. Flounder is a very mild white fish with a flaky texture and a clean flavor, so you don’t have to worry about a strong fishy flavor. The crispy topping adds a pop of extra flavor with thyme and parmesan, making it easy for everyone to enjoy. On top of all that, this flounder only takes about 20 minutes to make!
Looking to incorporate more easy fish recipes into your rotation? My Baked Alaska Pollock is very similar to this recipe with a few minor differences, and this Pan-Fried Flounder with creamy lemon caper sauce is great if you like sauces. I have also a lot of easy salmon recipes on the site! This Healthy Rice Bowl With Salmon is in our regular rotation here, and if you want to keep it real simple, this Miso Salmon is perfect.
Why You’ll Love This Recipe
- It’s easy—The prep is a breeze and the recipe calls for such simple ingredients, you might already have them kickin’ around!
- It’s quick—Just 20 minutes from start to finish. You could make this on even the busiest of weeknights.
- It’s tasty—The flavors here are simple, but tasty! A nice golden cheesy and herbaceous crust with a mild, tender fillet.
Ingredients for Baked Flounder Au Gratin
A full ingredient list with exact measurements can be found in the recipe card below.
- Panko—This type of bread crumb is heartier than Italian bread crumbs so holds up to moisture without getting soggy and keeps its crisp.
- Parmesan—I like using parm or pecorino romano because it’s doesn’t get stretchy when it melts, it simply adds a nice cheesy crust and a bit of saltiness.
Recipe Variations & Modifications
- Butter—For a nice buttery crumb, you could melt 1 TBSP of butter and stir it into the bread crumbs in place of the olive oil.
- Seasoning—Instead of dried thyme, you could use my homemade Italian seasoning. You could also swap the sea salt in the bread crumb mixture for a little garlic salt instead.
- Fish—This recipe works with any mild skinless and boneless white fish, like Alaska pollock, tilapia, cod, halibut, etc. Cooking times will vary, however, depending on the thickness of the fish.
How to Make Baked Flounder Au Gratin
Step 1. Preheat the oven to 400º F with the rack positioned in the middle. Gently blot the fillets with paper towels to rid of excess moisture, then season both sides of the fillets with sea salt and cracked black pepper. Set aside.
Step 2. In a small bowl, mix together 1 cup of bread crumbs, 2/3 cup of grated parmesan, 1 teaspoon of dried thyme, and about 1/2 teaspoon of sea salt. Stir it well to mix, then add 1 tablespoon of olive oil and stir until it’s well distribute—the bread crumbs will become darker in color and have a crumbly texture.
Step 3. Sprinkle the bread crumb mixture evenly over the fish and gently pat it down with your fingers. Pop it in the oven and bake the fish for 10-12 minutes, or until the fish is opaque, flakes easily with a fork, and reaches an internal temperature of 140° F. (You can check this with a meat thermometer.)
Step 4. Remove from the oven, garnish with finely chopped parsley, and serve with lemon wedges for a nice refreshing spritz!
Recipe Tip
If by the 10-minute mark your bread crumbs don’t seem to be turning a golden color, you can then switch to the broiler, on high, for just a minute or two. Just keep a close eye on them so they don’t burn.
How to Serve Baked Flounder Au Gratin
The mild flavors in this recipe allow for a variety of sides. These crispy Oven Roasted Mini Potatoes are a great option, as are these pub-style Air Fryer French Fries. Throughout the warmer months, we like to serve this fish with grilled asparagus. My Oven Roasted Broccoli with nutritional yeast is always great with its garlicky cheesy flavors, and if you’re into salad, you can’t go wrong with this loaded Greek Salad With Feta.
Storage & Reheating
- Leftover fillets will keep in the fridge in an airtight container for up to 4 days, but the texture quality will definitely decrease. I find that thin white fish fillets don’t hold up as well once refrigerated.
- To reheat, you can pop the fish in the microwave and reheat in 15-second increments until warmed through.
Frequently Asked Questions
Fish can be baked at anywhere from 350º F to 450ºF, depending on size and time you plan to spend baking. Be sure to always have a meat thermometer handy so you can check the internal temperature. Your fish should always be at about 140-145º F before taking it out of the oven.
This usually happens if you don’t pat your fish fillets with paper towels to remove excess moisture prior to cooking. Despite this seeming like a small task, it’s an important one!
When the fish reaches an internal temperature of 140-145º F.
No, there is no reason to rinse flounder fillets. This can actually spread bacteria by splashing is around.
More Easy Fish Recipes for Your Weeknights…
Fish and Seafood
Pan-Fried Flounder With Creamy Lemon Caper Sauce
Fish and Seafood
Sweet Chili Air Fryer Salmon Bites
Fish and Seafood
Chili-Seasoned Grilled Mahi Mahi Recipe
Fish and Seafood
Baked Cod With Tomato Herb Butter
If you try this baked flounder recipe, please pop back in and leave a 🌟 star rating and let us know how it went in the 📝 comments below.
20-Minute Baked Flounder au Gratin
Ingredients
- 4 flounder fillets, No flounder? You could use any white fish for this recipe.
- 2 TBSP extra virgin olive oil, divided, *See notes
- 1 cup panko breadcrumbs
- 2/3 cups freshly grated Parmigiano Reggiano cheese
- 1/2 tsp sea salt, more to taste
- 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
Instructions
- Preheat the oven to 400º F with the rack positioned in the middle.
- Gently blot the fillets with paper towels to rid of excess moisture, then season both sides of the fillets with sea salt and cracked black pepper. Set aside.
- In a small bowl, mix together 1 cup of bread crumbs, 2/3 cup of grated parmesan, 1 teaspoon of dried thyme, and about 1/2 teaspoon of sea salt. Stir it well to mix, then add 1 tablespoon of olive oil and stir until it’s well distribute—the bread crumbs will become darker in color and have a crumbly texture.
- Sprinkle the bread crumb mixture evenly over the fish and gently pat it down with your fingers. Pop it in the oven and bake the fish for 10-12 minutes, or until the fish is opaque, flakes easily with a fork, and reaches an internal temperature of 140° F.
- Remove from the oven, garnish with fresh chopped parsley, and serve with lemon wedges for a nice refreshing spritz!
Notes
- For a nice buttery crumb, you could melt 1 TBSP of butter and stir it into the bread crumbs in place of the olive oil.
- If by the 10-minute mark your bread crumbs don’t seem to be turning a golden color, you can then switch to the broiler, on high, for just a minute or two. Just keep a close eye on them so they don’t burn.
This recipe was so good, even picky eaters liked it. It had so much flavor and the crunchy topping was a big hit. Definitely going to be making this a regular meal choice. We had fresh lemons off the tree and that just added to the flavor, thanks for a great 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!