Quick Flounder Sandwich

There’s something about a fish sandwich that takes me right back to summer afternoons by the water. I’ve always loved how a simple piece of flounder can turn into such a satisfying meal with just a few basic ingredients. My kids used to be picky about seafood, but these sandwiches changed their minds completely – now they ask for them at least once a week!

I’ve found that flounder makes the perfect sandwich fish – it’s mild, flaky, and cooks up quickly. Plus, it’s a great way to get some seafood into your family’s diet without any fuss. When I’m short on time but want something that feels a bit special, this is my go-to recipe. The prep is simple, the cooking time is quick, and the cleanup is minimal.

Whether you’re new to cooking fish or just looking for an easy weeknight dinner, this flounder sandwich might become your new favorite. I like to set up a little topping station so everyone can customize their own – it makes dinner more fun and ensures everyone gets exactly what they want.

What Kind of Flounder Should I Use?

For a sandwich like this, any variety of flounder will work well, though summer flounder (also called fluke) is particularly good because of its mild, sweet flavor and firm texture that holds up nicely when fried. You’ll want to look for fillets that are translucent and have a fresh, mild smell – avoid any that appear dull or have a strong fishy odor. If you can’t find fresh flounder, frozen is perfectly fine, just make sure to thaw it completely in the refrigerator and pat it dry really well before breading. For the best results, try to choose fillets that are similarly sized so they’ll cook evenly and fit nicely on your sandwich bread.

Options for Substitutions

This sandwich recipe is pretty adaptable – here are some swaps you can try:

• Flounder fillets: Any mild white fish works great here – try cod, haddock, or even tilapia. Just make sure the fillets are similar in thickness to ensure even cooking.
• Bread-and-butter pickles: You can use dill pickles instead, or even sweet pickles. For the pickle juice, apple cider vinegar mixed with a little sugar works in a pinch.
• Panko breadcrumbs: Regular breadcrumbs can work, though the coating won’t be quite as crispy. You could also crush up cornflakes or even potato chips for a different kind of crunch.
• Pullman bread: Any sturdy sandwich bread will do – try sourdough, regular white bread, or even a soft roll. Just avoid very thin sliced bread as it might get soggy.
• Iceberg lettuce: Feel free to swap in romaine, green leaf lettuce, or even coleslaw mix. Each will give you a different but equally good crunch.
• Fresh dill: If you don’t have fresh dill, use 2 tablespoons dried dill instead. You could also try fresh parsley or chives for a different flavor.

Watch Out for These Mistakes While Cooking

The biggest challenge when frying flounder is temperature control – if your oil isn’t hot enough (around 350°F), you’ll end up with greasy, soggy fish instead of that perfect crispy coating. Another common mistake is overcrowding the pan, which drops the oil temperature and leads to uneven cooking – fry only one or two pieces at a time for the best results. To keep your breading from falling off, make sure to pat the fish completely dry before starting the dredging process, and let the breaded fillets rest for 5-10 minutes in the refrigerator to help the coating adhere better. For the crunchiest texture, avoid pressing down on the fish while it’s cooking, and transfer it to a wire rack instead of paper towels after frying – this prevents the bottom from getting soggy while it cools.

What to Serve With Flounder Sandwiches?

These crispy fish sandwiches are begging to be served with some classic seafood joint sides! Since you’ve already got potato chips in the recipe, go ahead and put out a big bowl of them for everyone to grab extra. A scoop of creamy coleslaw would be perfect here – the cool, crunchy cabbage goes so well with fried fish. You can also keep it simple with some pickle spears (since you’re already using pickle juice in the recipe) or a handful of sweet potato fries. If you’re feeling fancy, a small cup of tartar sauce on the side lets people add extra tang to their sandwiches.

Storage Instructions

Keep Fresh: The assembled sandwiches are best eaten right away while the fish is crispy. If you have leftover fried flounder, keep it in an airtight container in the fridge for up to 2 days. Store the prepared sauce separately in the fridge for up to 4 days, and keep the lettuce and other toppings in their own containers.

Prep Ahead: You can mix the sauce and slice the onions up to a day ahead – just keep them in separate containers in the fridge. The breading mixture can also be prepared in advance and stored in an airtight container at room temperature.

Crisp Up: To enjoy leftover fried flounder, heat it in a 350°F oven for about 5-7 minutes until warm and crispy. Avoid microwaving as this will make the breading soggy. Assemble your sandwich with fresh lettuce and toppings just before eating.

Preparation Time	15-30 minutes
Cooking Time	5-10 minutes
Total Time	20-40 minutes
Level of Difficulty	Medium

Estimated Nutrition

Estimated nutrition for the whole recipe (without optional ingredients):

• Calories: 3200-3600
• Protein: 80-90 g
• Fat: 220-250 g
• Carbohydrates: 300-350 g

Ingredients

• 1 small red onion, thinly sliced into rings
• 4 oz. bread-and-butter pickles, along with 1/2 cup of the pickle juice
• 3/4 cup mayonnaise
• 1/3 cup chopped fresh dill
• 2 teaspoons hot sauce
• 1 teaspoon ground black pepper
• 2 teaspoons lemon juice, with extra wedges for serving
• 1 tablespoon kosher salt, split
• 2 large eggs, whisked
• 1 1/2 cups panko breadcrumbs
• 1/2 cup all-purpose flour
• 2 flounder fillets (around 2/3 pound total), sliced in half diagonally
• 2/3 cup vegetable oil
• 3 cups finely shredded iceberg lettuce
• 8 slices of pullman bread
• 1 cup potato chips, plus additional for serving

Step 1: Prepare Onion Mixture and Dill Sauce

Combine sliced onion, chopped pickles, and pickle brine in a small bowl to create an onion mixture.

In a separate small bowl, mix together mayonnaise, fresh dill, hot sauce, ground pepper, 2 teaspoons of lemon juice, and ½ teaspoon of salt for the dill sauce.

These can be made a day ahead; just cover them and chill in the refrigerator.

Step 2: Bread the Fish Fillets

Set up a breading station with three shallow medium bowls: one with flour, the second with beaten eggs, and the third with panko bread crumbs.

Season each fish fillet with ½ teaspoon salt.

Dredge each fillet in flour, shaking off any excess.

Coat the fish with the egg, allowing any extra to drip off, followed by a coating of panko, pressing gently to make sure it adheres.

Place the breaded fish on a plate once done.

Step 3: Cook the Fish Fillets

Heat a generous amount of oil in a large skillet over medium heat.

Once the oil is hot, add the breaded fish fillets.

Cook until the breading is golden brown and the fish is cooked through, approximately 2–3 minutes for each side.

Transfer the cooked fish to a plate lined with paper towels to drain any excess oil.

Season all fillets with an additional ½ teaspoon of salt in total.

Step 4: Assemble the Sandwiches

Take your slices of bread and spread 1 heaping tablespoon of the prepared mayonnaise mixture on one side of each slice.

On the bottom slice, layer ¾ cup of lettuce, one cooked fish fillet, a small handful of potato chips, and ¼ cup of the onion and pickle mixture.

Close the sandwich with the top slice of bread, mayo side down.

Press down lightly to crush the potato chips for a bit of crunch.

Step 5: Serve the Sandwiches

Transfer the assembled sandwiches to a serving platter.

Repeat the assembly process for the remaining sandwiches.

Serve each sandwich with lemon wedges and additional potato chips on the side for extra enjoyment.