Baked Mahi Mahi with Fresh Blueberry Sauce

Are you looking for a quick seafood dinner that feels fresh, elegant, and easy enough for a weeknight? This baked mahi mahi recipe with blueberry sauce is a colorful, healthy, and delicious alternative to the more common mango or pineapple salsa pairings. The fish is mild, flaky, and buttery, while the sauce brings a bright sweet-tart finish that makes the whole dish feel special. It is simple to prepare, beautiful on the plate, and a great choice when you want to serve something impressive without spending hours in the kitchen.

What makes this baked mahi mahi with blueberry sauce stand out is the balance of flavor and presentation. The recipe is straightforward, but the finished dish looks vibrant and restaurant-worthy. Mahi mahi is a lean white fish with a firm texture and a clean, mild taste. It does not have a strong oily flavor, which makes it an excellent base for sauces, herbs, citrus, and light glazes.

Mahi mahi is also a good option when you want a lighter seafood meal. It bakes quickly, pairs well with rice or vegetables, and works beautifully with the lemon butter, garlic, thyme, and blueberry sauce used in this recipe. The Hawaiian meaning of mahi mahi is often described as “very strong,” referring to the fish itself, but the cooked fillets are tender, flaky, and delicate in flavor.

How to Make Baked Mahi Mahi with Blueberry Sauce

The Main Ingredients Needed

For the Blueberry Sauce:

• Butter – Adds richness and gives the sauce a smooth finish.
• Shallots and Garlic – These savory ingredients balance the sweetness of the blueberries and sugar. Shallots are milder than onions and bring a gentle sweetness to the sauce.
  • Shallots can often be used in recipes that call for onions when you want a softer flavor.
• Dry White Wine – A dry white wine such as chardonnay works well. Avoid sweet wine or table wine for this sauce.
• Freshly Squeezed Lemon Juice – Adds brightness and keeps the sauce from tasting too sweet.
• Granulated Sugar – Helps the blueberries release their juices and gives the sauce balance.
• Frozen Blueberries – Frozen blueberries are ideal for cooked sauces because they soften quickly and release plenty of juice.
• Cornstarch Slurry – A mixture of cornstarch and water thickens the blueberry sauce without making it heavy.

For the Baked Mahi Mahi:

• 5 or 6 ounce Mahi Mahi Fillets – You can also use another mild, firm fish such as halibut, sea bass, cod, rainbow trout, or salmon.
• Melted Butter – Helps keep the fish moist and flavorful as it bakes.
• Fresh Lemon Juice and Lemon Slices – Lemon juice flavors the butter sauce, while lemon slices bake on top of the fish.
• Thinly Sliced or Minced Garlic – Adds a savory layer to the mild fish.
• Sprigs of Thyme – Fresh thyme adds a light herbal aroma.

How to Make the Blueberry Sauce

This blueberry sauce is quick, simple, and full of flavor. It is especially good over baked mahi mahi, but it can also be served with other white fish, salmon, roasted chicken, pork chops, or pork loin. The sauce is lightly sweet, slightly tangy, and finished with savory shallots and garlic for depth.

Sauté the Shallots and Garlic. Heat a medium saucepan over medium heat and melt the butter. Add the sliced shallots and cook until tender and lightly browned, about two minutes. Add the minced garlic and cook briefly, no longer than one minute, so it does not burn or become bitter.

Add the Wine and Lemon Juice. Pour in the dry white wine and let it reduce until at least half of the liquid has evaporated. Reducing the wine concentrates the flavor and removes the harsh edge of the alcohol. Add the freshly squeezed lemon juice and stir.

• Why reduce the wine? Wine helps bring out the flavor of the other ingredients, but it should be cooked down so the sauce tastes smooth instead of sharp or boozy.
• For this blueberry sauce, the wine can be reduced until it is almost completely evaporated before adding the remaining ingredients.

Add the Sugar, Blueberries, and Slurry. Stir in the sugar until it dissolves completely. Add the frozen blueberries and cook over medium heat until the berries release their juices and the mixture reaches a low boil. Reduce the heat to a simmer. In a small bowl, mix equal parts cornstarch and water to make a slurry, then stir it into the sauce. Continue cooking until the sauce reaches your preferred thickness.

How To Prepare the Mahi Mahi

Rinse and Dry the Fillets. Quickly rinse the thawed mahi mahi under cold water, then pat each piece dry with paper towels. Drying the fish helps the butter mixture coat the fillets more evenly.

• How to thaw fish safely:
  • In the refrigerator: Remove the fish from its original vacuum package, place it in a zip-top bag on a plate, and refrigerate overnight until thawed.
  • In a bowl of cold water: Place the fish in a zip-top bag and submerge it in cold water until thawed. A small plate can help keep it underwater.
  • Do not thaw fish in the microwave.
  • Do not thaw fish on the countertop at room temperature.
• Can you bake mahi mahi from frozen? Yes. Remove it from the packaging, rinse, dry with paper towels, and follow the recipe. Add about 5 to 10 extra minutes to the baking time.

Place the Fillets in a Baking Dish. Line a shallow baking dish with parchment paper. Place the mahi mahi fillets on the parchment and season both sides with salt and pepper.

Make the Lemon Butter Sauce. Combine melted butter, lemon juice, and sliced or minced garlic. Brush the mixture over both sides of the fish. Top each fillet with lemon slices and fresh thyme sprigs.

How to Oven Bake Mahi Mahi

Mahi mahi can be pan-seared, grilled, broiled, or cooked in an air fryer, but baking is a great choice for this recipe. The gentle oven heat allows the lemon butter, garlic, and thyme to flavor the fish while keeping the fillets moist and flaky.

Bake in a preheated 425°F oven until the fish reaches an internal temperature of 137°F.

• How do you know when mahi mahi is done? The best way is to use an instant-read digital thermometer. Remove the fish from the oven when the internal temperature reaches 137°F.
• Do not overcook it. Mahi mahi cooks quickly. If it bakes too long, it can become tough and chewy instead of moist and flaky.

Serving the Mahi Mahi with Blueberry Sauce

This baked mahi mahi with blueberry sauce is delicious served over brown rice, which soaks up the lemon butter and sauce beautifully. It also pairs well with couscous, pearl couscous, quinoa, roasted asparagus, roasted vegetables, or a simple green salad. For a clean and colorful presentation, spoon the blueberry sauce over the fish just before serving.

• Garnish: Sprinkle chopped fresh parsley over the top and add a small lemon wedge to each fillet. The deep blueberry sauce, fresh herbs, and lemon make the dish bright and elegant.

More Seafood Recipe Ideas

Shrimp Scampi with Spinach and Tomatoes

Pan-Seared Salmon with Creamy Mustard Sauce

Asian Seared Tuna with Spicy Peanut Sauce

Pan-Seared Salmon with Fruit Salsa

Cast Iron Salmon in Orange Sauce