Name: Blackened Mahi Mahi with Cajun Seasoning Recipe
Prep time: 10 min
Cook time: 5 min
Total time: 15 min
Cuisine: Southern
Ingredients: ¾ teaspoon onion powder; ½ teaspoon coconut sugar or brown sugar (optional); ½ teaspoon smoked paprika; ½ teaspoon chili powder; ½ teaspoon garlic powder; ½ teaspoon dried basil; ½ teaspoon dried thyme; Salt and freshly cracked black pepper, to taste; 2 mahi mahi fillets (about 6 ounces each); 1 tablespoon olive oil; Lemon wedges, for serving

Jump to Recipe· 3.8 from 30 reviews

If you’re craving a dish that’s bursting with bold flavors and can be whipped up in no time, the Blackened Mahi Mahi with Cajun Seasoning Recipe is your new best friend in the kitchen. This dish brings together the flaky, mild sweetness of mahi mahi and a bright, smoky Cajun spice blend that adds just the right amount of heat and complexity. Perfect for a quick weeknight dinner or impressing guests, it’s a celebration of Southern-inspired zest, all in about 15 minutes from start to finish.

Ingredients You’ll Need

The image shows a white plate with four pieces of raw, pale pink fish fillets layered slightly overlapping each other, with some visible white marbling and light reddish streaks. To the top left is a white plate with five lemon wedges arranged in a loose circle. Above the fish plate is a small clear glass bowl filled with golden yellow oil. The setup is placed on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Getting the perfect balance of flavor begins with a handful of simple, thoughtfully chosen ingredients. Each one plays a vital role, from the aromatic herbs to the rich paprika, ensuring every bite is packed with layers of taste and color that make this meal unforgettable.

Onion powder: adds a subtle sweetness and depth to the spice mix, essential for that classic Cajun flavor.
Coconut sugar or brown sugar (optional): a hint of sweetness helps to balance the spices and create a beautiful caramelized crust.
Smoked paprika: the smoky undertone it’s the heart of the blackening rub, infusing warmth and color.
Chili powder: brings a gentle kick without overpowering, enhancing both heat and complexity.
Garlic powder: a must-have to add savory richness and boost the aromatic profile of the seasoning.
Dried basil: offers a slightly sweet, peppery note that brightens the mix.
Dried thyme: brings earthiness and herbaceous depth, rounding out the flavors perfectly.
Salt and freshly cracked black pepper: foundational seasonings to elevate every component of the dish.
Mahi mahi fillets: a firm, mild-bodied fish that holds up beautifully under the robust spice crust.
Olive oil: for searing the fish to a crisp, flavorful blackened finish.
Lemon wedges: a zesty, fresh contrast to the spicy crust that brightens each bite.

How to Make Blackened Mahi Mahi with Cajun Seasoning Recipe

Step 1: Prepare the Spice Mix

Start by combining the onion powder, optional coconut sugar, smoked paprika, chili powder, garlic powder, dried basil, and dried thyme in a shallow bowl. This blend is the soul of the Blackened Mahi Mahi with Cajun Seasoning Recipe. Mixing these spices beforehand lets their flavors meld together, creating a vibrant rub that will coat the fish beautifully.

Step 2: Season the Mahi Mahi

Pat your mahi mahi fillets dry with paper towels to ensure the seasoning sticks properly and the fish sears nicely. Sprinkle salt and freshly cracked black pepper on both sides, then generously coat each fillet with your homemade Cajun spice mixture. This step is crucial for building that irresistible blackened crust everyone loves.

Step 3: Cook the Fish to Perfection

Heat olive oil in a skillet over medium-high heat until shimmering. Carefully add the seasoned mahi mahi fillets and cook them for 2 to 3 minutes per side. The high heat sears the spice rub, creating a beautiful, flavorful crust while locking in moisture. You’ll know it’s done when the internal temperature reaches 130°F to 137°F or when the fish flakes easily and turns opaque.

Step 4: Rest and Serve

Once cooked, remove the fillets from the heat and let them rest for a few minutes. This short pause allows the juices to redistribute for maximum tenderness. Serve warm, drizzled with fresh lemon juice to add brightness that perfectly complements the Blackened Mahi Mahi with Cajun Seasoning Recipe’s spicy, smoky profile.

How to Serve Blackened Mahi Mahi with Cajun Seasoning Recipe

The dish is presented on a white scalloped plate with three main layers: the bottom layer is a bed of fluffy white rice with separate grains, the middle layer is a thick, well-seasoned piece of golden-brown grilled fish fillet with a slightly charred and textured surface, and the top layer is a bright yellow mango salsa mixed with small pieces of red onion and green herbs, placed at the center of the fish. On the side of the plate, two lemon wedges rest next to the fish, adding a fresh yellow color contrast. The background features a white marbled texture with some hints of green cilantro leaves visually scattered around, and a soft fabric in blue and white tones is partially visible at the bottom left corner. Photo taken with an iphone --ar 4:5 --v 7

Garnishes

Simple garnishes can make your presentation pop and add an extra layer of flavor. Fresh lemon wedges are a classic, their citrus notes cutting through the spice. Sprinkle some finely chopped parsley or green onions for a vibrant splash of color and freshness. A dollop of cool sour cream or a tangy remoulade sauce can also balance the heat beautifully.

Side Dishes

The versatility of the Blackened Mahi Mahi with Cajun Seasoning Recipe means it pairs wonderfully with a variety of sides. Creamy coleslaw or a crisp garden salad bring refreshing contrast, while buttery corn on the cob or fragrant jasmine rice complement the seafood without competing. For a soul-food twist, try it alongside creamy macaroni and cheese or smoky black beans.

Creative Ways to Present

Elevate your dish by serving your blackened mahi mahi over a bed of garlic mashed potatoes or tucked into a warm tortilla with cabbage slaw and avocado for a delightful fish taco. Drizzle with a spicy aioli or a squeeze of fresh lime for an extra zing. Turning this recipe into a vibrant bowl or sandwich offers new textures and flavors while keeping the essence of the Blackened Mahi Mahi with Cajun Seasoning Recipe alive.

Make Ahead and Storage

Storing Leftovers

If you have any leftovers of this delicious dish, store the cooked mahi mahi in an airtight container in the refrigerator. It will stay fresh for up to 2 days. Be sure to let the fish cool before sealing to prevent condensation, which can affect the texture.

Freezing

While it’s best enjoyed fresh, you can freeze cooked blackened mahi mahi for up to 1 month. Wrap each fillet tightly in plastic wrap and then place them in a freezer-safe bag or container. When you’re ready to enjoy it again, thaw overnight in the fridge before reheating gently.

Reheating

To reheat, warm your fish gently in a skillet over low heat or in the oven at 275°F until heated through. Avoid the microwave, as it can dry out the fish and make the beloved blackened crust soggy. Adding a light drizzle of olive oil helps revive that crispy outer layer.

FAQs

Can I use other types of fish for this recipe?

Absolutely! While mahi mahi is ideal for its firm texture and mild flavor, you can substitute with other sturdy white fish like swordfish, snapper, or even cod. Just be mindful of cooking times, as thinner fillets cook faster.

Is the Cajun seasoning very spicy?

The Cajun seasoning in this recipe has a balanced heat level that provides warmth without overwhelming the palate. If you prefer less spice, simply reduce the chili powder or leave out any additional optional spicy seasonings.

Do I need a special pan to blacken the fish?

No special pan is required, but using a heavy skillet such as cast iron helps achieve that beautifully blackened crust. The even heat retention ensures the spices caramelize perfectly.

Can I prepare the spice mix in advance?

Yes! The spice mix can be made ahead and stored in an airtight container for several weeks. This makes dinner prep super quick and keeps the flavors fresh and vibrant.

How can I tell when the mahi mahi is fully cooked?

The best indicators are an internal temperature between 130°F to 137°F or when the fish flakes easily with a fork and is opaque throughout. Overcooking will dry out the fish, so watch it closely.

Final Thoughts

The Blackened Mahi Mahi with Cajun Seasoning Recipe is a true gem for anyone seeking a recipe that’s quick, flavorful, and satisfying. It turns simple ingredients into a restaurant-quality meal with a deliciously spicy kick. Give this a try soon—you might just find it becoming a fast favorite that brings the vibrant spirit of Cajun cooking right to your table.

Blackened Mahi Mahi with Cajun Seasoning Recipe

Ingredients You’ll Need