A homemade Cajun spice mix adds incredible flavor to this Blackened Mahi Mahi. It’s a quick dish you can easily pull together on a busy weeknight but it’s so tasty you’ll want to serve it to guests!
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This is a new recipe for me and it came about after Paul and I had a meal at a nearby restaurant. We both ordered the mahi mahi special that was served with mashed sweet potatoes and veggies, and then we basically freaked out about how good it was for at least two days after and it haunted us in our dreams…. we’re weird.
This all had me wondering why the heck I never make mahi mahi at home. So, of course, I had to make some mahi mahi.
I set out to capture the same flavors we had in the restaurant dish and knew I definitely had to pair it with sweet potatoes, just like they did. The sweetness perfectly complements the slightly spicy fish in a soul-satisfying way. It’s truly a perfect flavor combination and it also happens to be SO good for us.
Say hello to my new favorite item from Costco. This great big package of Wild Caught Mahi Mahi contains skinless, individually vacuum-packed portions of incredibly fresh mahi mahi. I pop this bag in my freezer and pull just the number I need. The fish is FRESH, people. There is zero fishy aroma in the house after cooking it.
Mahi Mahi is a mild, firm textured white fish that is wonderfully tender – almost buttery – when prepared properly. It’s a fabulous source of lean protein and packed with nutrition. If you’ve got young ones who are squeamish about seafood, this would be a great one to try on them. Yes, blackened fish can be quite spicy. but when you make your own spice mix you get to decide precisely how spicy you’d like it. I’ll show you how!
To make the Kickin’ Cajun Seasoning Mix, grab a small bowl and combine 1½ teaspoons onion powder – 1 teaspoon each of smoked paprika, oregano, granulated garlic or garlic powder, thyme, and salt – and ½ teaspoon each of black pepper and cayenne pepper. The only spicy item here is the cayenne so feel free to adjust the amount to suit your taste. At ½ teaspoon, the fish will be mild to moderate on the spice scale. I’m a bit of a wimp and it is perfect for me. If I had little ones, I’d reduce it to ¼ teaspoon or even eliminate it all together. My big boys would tell me to add more!
Update – By popular demand I’ve published a recipe for a big batch of the Kickin’ Cajun Seasoning Mix. Check out the post for other delicious ways you can use this flavor-packed blend.
If you are using frozen mahi mahi, be sure to allow it to thaw completely (24 hours) in the refrigerator. Pat the fillets dry with paper towels so the spice mix will adhere nicely.
Sprinkle both sides of the fillets with the spice mix and use your clean hands to pat the mixture into the flesh of the fish. Then, of course, wash those hands again.
Melt 2 tablespoons butter and 1 tablespoon olive oil in a large skillet over medium-high heat. Get the pan as hot as it can get, without burning the butter, and then add the seasoned mahi mahi. You want that nice sizzle when the fish hits the pan. Cook it a good 3 or 4 minutes on one side until nicely golden brown, then flip it and let it go a few minutes on the other side. You don’t want to overcook it so be vigilant and pull the pan off the heat just as soon as it’s cooked through and flakes easily with a fork.
Remove the fish to a serving platter and squeeze fresh lemon juice over the top. A little citrus is a necessary thing when cooking fish as far as I’m concerned.
Oh, and before I go, if you’d like to serve this with mashed sweet potatoes, here’s how I did it. Place a couple of red-skinned sweet potatoes in a large pot and cover with water. Bring to a boil, reduce the heat and bring the water to a nice simmer and cover the pot. Cook the potatoes for 45 minutes to an hour, or until they pierce easily through with a knife. Remove from the pot to cool for just a couple of minutes. Use paper towels to pull the skin off and then mash the potatoes with a touch of light sour cream and salt. Perfect every time.
If you love mahi mahi, be sure to check out my Mahi Mahi with Lemon Butter Sauce. It has an entirely different but utterly delicious flavor profile.
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Blackened Mahi Mahi
Video
Ingredients
- 4 mahi mahi fillets, approximately 6 ounces each
- 2 tablespoons butter
- 1 tablespoon olive oil
- 1 lemon
Kickin’ Cajun Seasoning Mix:
- 1 ½ teaspoons onion powder
- 1 teaspoon garlic powder
- 1 teaspoon smoked paprika
- 1 teaspoon dried thyme leaves
- 1 teaspoon dried oregano leaves
- 1 teaspoon fine grain sea salt
- ½ teaspoon freshly ground black pepper
- ½ teaspoon cayenne pepper, or to taste
Instructions
- Combine all Kickin’ Cajun Seasoning Mix ingredients in a small bowl.
- Pat fillets dry with paper towels. Season the fillets liberally with Kickin’ Cajun Spice Mix on both sides, pressing the seasoning into the fish with your hands. Wash hands thoroughly.
- Place a large saute pan over medium-high heat and add butter and oil. When the fat is nice and hot, add the seasoned fish. Cook, undisturbed, for several minutes, until golden brown on one side. Flip fish over and continue to cook until opaque and completely cooked through.
- Squeeze lemon juice over the fish and serve.
Notes
Nutrition
Nutrition information is automatically calculated using generic ingredients, and is an estimate not a guarantee. For more accurate results, please refer to the labels on your ingredients at home.
Like this? Please rate & comment below!
I’ve been looking for a blackened mahi recipe, and this one nailed it! Not to much pepper, not hot, but just a hint of blackened.
My two sons who aren’t big fish eaters wanted more!
I served the fish over a coconut rice with a drizzle of a homemade sweet ginger soy sauce with a sweet potato and asparagus side.
It was excellent!
LOVE this fish with coconut rice! So happy to hear your boys loved it. Thanks so much for your comment, BH 🙂
This was so good! The dish was better than I’ve had at very expensive restaurants and easy to prepare,. My picky eater sweetheart loved it. Thanks.
This was fabulous. I was looking for a recipe for mani mahi with more flavor than just lemon and garlic. This so delivered. A new family favorite.
The best recipe ever! I have made this several times in the past few weeks and my husband LOVES it! He will request this recipe specifically! Thank you so much for sharing!
So glad it’s working so well for you! Thanks for your comment, Alexis 🙂
my 15 yo loved it, my husband who is not a fish eater actually ate the fish and i loved it! so simple, so good!
The whole family loved this one! Not too spicy it was just right I had a little spice left over and I put it on the green beans that I tossed with oo and baked at 350. I was told by my wife and kids to print and make it again soon folder
Followed directions as given, flipped at 3 minutes and cooked for 3 minutes more on a medium cast iron pan.
Crust turned out great but fish was dry and a bit overdone, what went wrong?
I’m sorry it didn’t turn out well for you. I’m surprised it was overcooked at 3 minutes per side. Mahi mahi filets are typically pretty thick and meaty but I would just recommend cutting down on the cooking time if you try it again.
I just made this for my very picky son and he LOVED it! I highly recommend and will be making this recipe again.
My husband and I loved this recipe! It tastes like the blackened mahi at our local seafood restaurant.
My wife and son hate fish, but let me try out this recipe. I’m so glad they did because it was really delicious and they loved it!! Their plates were empty. Will definitely make again, thanks for the recipe.
Seasoning is perfectly balanced (I doubled the cayenne which made it medium-hot to my pallete). The cook time will vary based on the thickness of your filets. Mine took much longer than the author recommended. I suggest using an instant read thermometer, and make sure the fish gets to 125-130 degrees. FDA recommends 145, that’s overcooked and you’ll hate the taste and texture at that temp. My filets were thick and took about 7-8 minutes to get there. I flipped them twice, to allow even blackening on both sides. Also, make sure you hit it with lemon just before you remove the fish from the pan as suggested, it really brightens up the flavor. Make this for people who say they don’t like fish. Thanks for the perfect seasoning!!
I’ve never cooked mahi before and was worried I’d mess it up. This recipe though made it so easy and unbelievably tasty! I had it with some steamed fresh green bean tossed in a little EVOO, sea salt, and fresh cracked pepper. Complimented the fish very well! This is a keeper recipe for me!