Flavorful Flounder with Tomatoes Recipe

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I always thought fish was tricky to cook until I learned this simple method with flounder and tomatoes. Growing up, the only fish we had came from the frozen food section, usually overdone and a bit rubbery. My mom wasn’t big on seafood, so we stuck to what she knew.

But here’s the thing about flounder – it’s actually one of the easiest fish to get right, especially when you pair it with tomatoes. The tomatoes do most of the work, keeping the fish moist while it cooks and adding just enough flavor without overwhelming the mild fish. Now it’s one of those dishes I make when I want something good without much fuss.

What Kind of Flounder Should I Use?

When shopping for flounder, you’ll typically find either summer flounder (also called fluke) or winter flounder at your local fish counter. Both types work great for this recipe, though summer flounder tends to be slightly thicker and meatier. Look for fillets that are firm to the touch and have a mild, fresh smell – any strong fishy odor is a red flag. Fresh flounder should appear translucent and have a pinkish-white color, without any brown spots or yellowing edges. If you can’t find fresh flounder, frozen fillets can work well too – just make sure to thaw them completely in the refrigerator overnight and pat them dry before cooking.

Options for Substitutions

This Mediterranean-style fish dish is pretty flexible with substitutions. Here’s what you can swap if needed:

• Flounder: While flounder has a mild, sweet taste, you can use other white fish fillets like sole, tilapia, or cod. Just adjust cooking time based on the thickness of your fish – thicker fillets might need a few extra minutes.
• Plum tomatoes: Can’t find plum tomatoes? Regular tomatoes work fine – just remove some seeds to avoid excess liquid. In a pinch, you can use a 14-oz can of diced tomatoes, drained.
• Kalamata olives: Any black or purple olives will work here. If you’re not an olive fan, you can leave them out completely.
• White wine: Replace with chicken broth or fish stock, plus a splash of lemon juice to add some brightness.
• Capers: If you don’t have capers, try finely chopped green olives for that briny taste, or simply skip them.
• Fresh basil: In winter months when fresh basil is harder to find, you can use 1 teaspoon dried basil, or try fresh parsley for a different but still tasty herb option.

Watch Out for These Mistakes While Cooking

The biggest challenge when cooking flounder is its delicate texture – overcooking can quickly turn this fish from tender to tough and rubbery, so aim to cook it just until it flakes easily with a fork, usually 3-4 minutes per side. A common mistake is adding the fish too early in the cooking process – make sure to prepare your tomato sauce first, as the fish cooks very quickly and shouldn’t wait around. For the best results, pat the flounder fillets completely dry before cooking to ensure proper browning and prevent them from steaming instead of searing. When flipping the fish, use a wide spatula and turn it gently to keep the fillets intact, as flounder can easily break apart during cooking. To maintain the perfect balance of flavors, add the fresh basil only in the final minute of cooking – this preserves its fresh taste and aroma while still allowing it to complement the dish.

What to Serve With Flounder?

This Mediterranean-style flounder pairs perfectly with a side of fluffy couscous or orzo pasta to soak up all those tasty tomato and wine juices. For a fresh veggie option, try serving it with roasted asparagus or a simple arugula salad dressed with lemon and olive oil – the peppery greens complement the mild fish really well. If you’re looking to keep things light and low-carb, a side of sautéed zucchini or steamed green beans works great too. You might also want to have some crusty bread on the table to mop up the sauce (trust me, you won’t want to leave any behind!).

Storage Instructions

Keep Fresh: If you have any leftover flounder with tomatoes, place it in an airtight container and pop it in the fridge. It’ll stay good for up to 2 days, though fish dishes are usually best enjoyed the same day they’re made. The flavors actually develop nicely overnight!

Make Ahead: You can prep the tomato sauce up to a day in advance – just store it in the fridge and reheat gently before adding the fish. This makes dinner prep super quick when you’re ready to cook the flounder.

Warm Up: To enjoy any leftovers, gently warm them in a covered skillet over low heat until just heated through, usually about 3-4 minutes. Be careful not to overheat, as this can make the fish tough. The microwave works too – just use 50% power in short bursts.

Preparation Time	15-25 minutes
Cooking Time	30-40 minutes
Total Time	45-65 minutes
Level of Difficulty	Medium

Estimated Nutrition

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

• Calories: 700-800
• Protein: 50-60 g
• Fat: 40-50 g
• Carbohydrates: 30-35 g

Ingredients

• 5 plum tomatoes (roma)
• 2 tablespoons extra virgin olive oil
• Half a spanish onion, diced
• 2 garlic cloves, minced
• A pinch of italian herbs
• 24 kalamata olives, pitted and diced
• 1/4 cup white wine
• 1/4 cup capers
• 1 teaspoon squeezed lemon juice
• 6 basil leaves, chopped
• 3 tablespoons grated parmesan cheese
• 1 pound flounder fillets
• 6 basil leaves, torn into pieces

Step 1: Prepare the Tomatoes

Preheat your oven to 425 degrees F (220 degrees C).

Bring a saucepan of water to a boil.

Carefully plunge the tomatoes into the boiling water for a brief moment, then immediately transfer them to a medium bowl of ice water to cool.

Once cooled, drain the tomatoes, peel off and discard the skins, and chop the tomatoes.

Set them aside for later use.

Step 2: Cook the Tomato Sauce

In a skillet, heat olive oil over medium heat.

Add the onion and sauté until tender, about 5 minutes.

Stir in the chopped tomatoes, garlic, and Italian seasoning, and cook for 5 to 7 minutes until the tomatoes become tender.

Mix in olives, wine, capers, lemon juice, and half of the basil leaves.

Reduce the heat, blend in Parmesan cheese, and cook the mixture until it reduces to a thick sauce, about 15 minutes.

Step 3: Prepare the Flounder for Baking

Arrange the flounder fillets in a shallow baking dish, making sure they are evenly spread out.

Pour the thickened sauce over the fillets, distributing it evenly so each fillet is covered with the flavorful mixture.

Top with the remaining basil leaves.

Step 4: Bake the Flounder

Place the baking dish in the preheated oven and bake for about 12 minutes, or until the fish is easily flaked with a fork.

Ensure that the fish is cooked through by checking the texture—it should be opaque and tender.

Step 5: Serve the Dish

Once the flounder is cooked, remove it from the oven and let it cool slightly before serving.

Enjoy this delicious flounder dish, enhanced with a rich and savory tomato sauce, as a delightful meal.