Baked Mahi-Mahi with Garlic-Herb Butter

Baked Mahi-Mahi with Garlic-Herb Butter is a vibrant, health-conscious dish that brings together the delicate, flaky texture of fresh mahi-mahi with the bold, aromatic flavors of garlic, lemon, and a medley of fresh herbs. This recipe is perfect for seafood lovers seeking a light yet satisfying meal that’s both easy to prepare and rich in flavor. Whether you’re cooking for a weeknight dinner or hosting a special gathering, this dish delivers restaurant-quality results with minimal effort. With its golden-brown crust, tender interior, and luxurious herb butter sauce, it’s sure to impress even the most discerning palates.

The History

Mahi-mahi, whose name means “strong-strong” in Hawaiian, has long been a staple in Pacific Islander and Latin American cuisines. Known as dolphinfish (not to be confused with dolphins), this fish thrives in warm offshore waters around the world and is prized for its firm texture and mild, slightly sweet taste. Historically, coastal communities have grilled or seared mahi-mahi over open flames, often seasoned simply with salt, citrus, and herbs. The practice of baking fish with butter and herbs, however, traces back to European culinary traditions—particularly French and Mediterranean cooking—where butter-based sauces like beurre blanc and beurre noisette were used to enhance delicate seafood. Over time, these techniques merged with island-inspired flavors, giving rise to modern dishes like Baked Mahi-Mahi with Garlic-Herb Butter. Today, this fusion of cultures and techniques celebrates the best of both worlds: simplicity, freshness, and bold taste.

Ingredients Breakdown

The beauty of this dish lies in its balance of high-quality ingredients that each play a vital role:

Mahi-Mahi Fillets: Choose fresh, skinless fillets that are about 6–8 ounces each and 1 inch thick. The fish should smell clean and oceanic, not fishy, and appear moist with a slight pink or grayish hue depending on the cut.
Unsalted Butter: Using unsalted butter allows you to control the salt level. It melts into a rich, creamy base that carries the flavors of garlic and herbs.
Fresh Garlic: Minced garlic adds pungency and depth. Fresh is essential—avoid jarred or powdered versions for optimal aroma and taste.
Fresh Herbs: A combination of parsley, thyme, and dill provides brightness and complexity. Parsley offers a clean finish, thyme adds earthiness, and dill contributes a subtle anise-like note that complements the fish beautifully.
Lemon: Both juice and zest are used. The acid from the lemon brightens the butter, cuts through richness, and enhances the natural sweetness of the fish.
Olive Oil: Used to lightly coat the baking dish and prevent sticking, while adding a fruity undertone.
Seasonings: Kosher salt and freshly ground black pepper are crucial for enhancing all the other flavors without overpowering the delicate fish.
Panko Breadcrumbs (Optional): For those who enjoy a bit of crunch, a light sprinkle of panko creates a golden crust when baked.

Step-by-Step Recipe

Preheat the Oven: Set your oven to 375°F (190°C). This temperature ensures gentle, even cooking that preserves moisture while allowing the butter to caramelize slightly on the surface.
Prepare the Baking Dish: Lightly grease a glass or ceramic baking dish with olive oil to prevent sticking. Alternatively, line it with parchment paper for easier cleanup.
Season the Fish: Pat the mahi-mahi fillets dry with paper towels—this helps the seasoning adhere and promotes better browning. Season both sides generously with kosher salt and freshly ground black pepper.
Make the Garlic-Herb Butter: In a small saucepan over low heat, melt 6 tablespoons of unsalted butter. Add 4 cloves of minced garlic and sauté for 1–2 minutes until fragrant but not browned. Remove from heat and stir in 2 tablespoons of fresh lemon juice, 1 teaspoon of lemon zest, 2 tablespoons chopped fresh parsley, 1 tablespoon chopped fresh thyme, and 1 tablespoon chopped fresh dill. Mix well.
Arrange the Fillets: Place the seasoned fillets in the prepared baking dish in a single layer, leaving space between each for proper air circulation.
Top with Butter Mixture: Spoon the warm garlic-herb butter evenly over each fillet, making sure to drizzle some into the crevices so every bite is flavorful.
Add Optional Crunch (if using): For a crisp topping, sprinkle 2–3 tablespoons of panko breadcrumbs over each fillet after applying the butter.
Bake: Transfer the dish to the preheated oven and bake for 15–18 minutes, depending on thickness. The fish is done when it flakes easily with a fork and reaches an internal temperature of 145°F (63°C).
Rest and Garnish: Let the fish rest for 2–3 minutes after removing from the oven. This allows the juices to redistribute. Finish with a final sprinkle of fresh herbs and a squeeze of fresh lemon juice before serving.

Tips

Don’t Overcook: Mahi-mahi can become dry if baked too long. Keep a close eye during the last few minutes of cooking. The flesh should be opaque throughout but still moist.
Use Fresh Ingredients: Fresh garlic and herbs make a dramatic difference. Dried herbs lack the vibrancy needed to elevate this dish.
Butter Temperature: Warm the butter gently. Boiling or browning it too much can create a bitter taste that overwhelms the fish.
Elevate the Fillets: Place the fish on a bed of sliced lemons, onions, or fennel. This lifts the fillets slightly, allowing steam to circulate and preventing sogginess on the bottom.
Serve Immediately: This dish is best enjoyed hot out of the oven when the butter is glossy and the fish is tender.
Double the Butter Sauce: Consider making extra garlic-herb butter—it’s delicious drizzled over rice, potatoes, or roasted vegetables.

Variations and Customizations

This recipe is highly adaptable to suit different tastes and dietary needs:

Cajun-Style: Add 1 teaspoon of smoked paprika, ½ teaspoon of cayenne pepper, and a pinch of oregano to the butter for a spicy kick.
Mediterranean Twist: Incorporate chopped sun-dried tomatoes, Kalamata olives, and capers into the butter mixture, and substitute rosemary for dill.
Dairy-Free Option: Replace butter with high-quality olive oil or a plant-based butter alternative. Add 1 tablespoon of nutritional yeast for a richer, umami depth.
Gluten-Free: Omit panko or use gluten-free breadcrumbs if desired for a crunchy topping.
Citrus Variations: Swap lemon for lime or orange, especially if pairing with tropical salsas or mango avocado salads.
Grilled Version: Instead of baking, grill the marinated fillets over medium heat for 4–5 minutes per side. Use foil or a fish basket to prevent sticking.
Stuffed Mahi-Mahi: Butterfly the fillets and stuff them with spinach, cream cheese, and sun-dried tomatoes before baking with the herb butter.

Health Considerations and Nutritional Value

Baked Mahi-Mahi with Garlic-Herb Butter is not only delicious but also nutritionally beneficial:

Lean Protein Source: Mahi-mahi is low in fat and high in protein, providing approximately 20–25 grams of protein per 6-ounce serving, which supports muscle repair and satiety.
Rich in Selenium and Niacin: This fish is an excellent source of selenium, an antioxidant that supports thyroid function, and niacin (vitamin B3), which aids metabolism and nervous system health.
Omega-3 Fatty Acids: While not as high as fatty fish like salmon, mahi-mahi still contains beneficial omega-3s that support heart and brain health.
Moderate Calorie Count: A serving of this dish (including 2 tbsp herb butter) contains roughly 280–320 calories, making it suitable for balanced diets.
Heart-Healthy Fats: Olive oil and moderate butter use contribute monounsaturated fats and flavor without excessive saturated fat—especially when consumed in moderation.
Dietary Notes: Naturally gluten-free (if breadcrumbs are omitted), low-carb, keto-friendly, and Whole30-compliant (with dairy substitutions).
Mercury Levels: Mahi-mahi is considered a moderate-mercury fish. It’s safe for most adults to consume 2–3 servings per week, but pregnant women and young children should limit intake to one serving weekly according to FDA guidelines.

Ingredients

4 mahi-mahi fillets (6–8 oz each, about 1 inch thick)
6 tablespoons unsalted butter
4 cloves garlic, minced
2 tablespoons fresh lemon juice
1 teaspoon lemon zest
2 tablespoons fresh parsley, finely chopped
1 tablespoon fresh thyme leaves
1 tablespoon fresh dill, chopped
2 tablespoons olive oil (for greasing)
Kosher salt, to taste
Freshly ground black pepper, to taste
3 tablespoons panko breadcrumbs (optional, for topping)
Additional lemon wedges, for serving
Extra fresh herbs, for garnish

Directions

Preheat oven to 375°F (190°C). Lightly grease a 9×13-inch baking dish with olive oil or line with parchment paper.
Pat mahi-mahi fillets dry with paper towels. Season both sides with salt and pepper and place in the baking dish.
In a small saucepan, melt butter over low heat. Add minced garlic and cook for 1–2 minutes until fragrant. Do not let it brown.
Remove from heat. Stir in lemon juice, lemon zest, parsley, thyme, and dill. Mix well to combine.
Spoon the garlic-herb butter mixture evenly over each fillet, coating the top thoroughly.
If using panko, sprinkle about 1–2 teaspoons over each fillet for a light, crispy topping.
Bake for 15–18 minutes, or until the fish is opaque and flakes easily with a fork. Internal temperature should reach 145°F (63°C).
Remove from oven and let rest for 3 minutes. Garnish with additional fresh herbs and serve immediately with lemon wedges on the side.
Drizzle any remaining butter sauce from the pan over the fillets before serving for extra flavor.

FAQ

Can I use frozen mahi-mahi?
Yes, but thaw the fillets completely in the refrigerator overnight before cooking. Never cook frozen fish directly, as it will release excess moisture and result in uneven texture.

What can I serve with this dish?
Excellent pairings include roasted asparagus, garlic mashed potatoes, quinoa, wild rice pilaf, grilled zucchini, or a fresh arugula salad with citrus vinaigrette.

Can I make this ahead of time?
You can prepare the herb butter up to 2 days in advance and store it in the fridge. Reheat gently before using. However, assemble and bake the fish just before serving for best results.

Is mahi-mahi sustainable?
In the U.S., wild-caught mahi-mahi from troll or pole-and-line fisheries is generally considered sustainable. Look for certifications like MSC or Seafood Watch recommendations to ensure responsible sourcing.

Can I use dried herbs instead of fresh?
While possible, dried herbs are more concentrated and lack the brightness of fresh ones. If substituting, use one-third the amount (e.g., 1 teaspoon dried parsley instead of 1 tablespoon fresh) and add them to the melted butter off the heat to rehydrate.

How do I store leftovers?
Store cooled leftovers in an airtight container in the refrigerator for up to 2 days. Reheat gently in the oven at 300°F or enjoy cold in salads. Avoid microwaving, as it can make the fish rubbery.

Summary

Baked Mahi-Mahi with Garlic-Herb Butter is a simple yet elegant dish that highlights the natural flavor of fresh fish with a luxurious blend of aromatic herbs, citrus, and rich butter. Quick to prepare and full of nutritious benefits, it’s a wholesome, gourmet-worthy meal perfect for any occasion.