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 use this seasoning mix on tilapia all the time! It’s my favorite!
Without a doubt, the best blackened Mahi recipe you can ask for. Follow the Kickin Cajun recipe to the “T”.
My wife, who doesn’t particularly like fish did enjoy this recipe. The flavor of the rub disgused the taste of the fist and she particularly liked the crunch of the blackened topping. I also liked it quite well. I would have liked a little more spice, but I backed off on the cayene since she doesn’t like heat in her food as much as I do. Overall, it met both of our standards and now it’s in my recipe collection.
This will be a keeper recipe–easy to make with pantry staples and it turned out perfectly! I think I’ll cut back on the salt a bit next time though.
This was so good!! I have never attempted to make blackend fish but after looking at your recipe, I was hooked!! (Pun intended)😁. It came out amazing!!!! My husband said he is never eating fish out again he liked it that much!! I was afraid it would be dry but it was very moistThank you!!
FANTASTIC recipe and we have SO enjoyed our Mahi dinners after finding this amazing recipe THANK YOU!!
What a great quick and easy recipe, using herbs I’m likely to have on-hand! Thanks you for helping me learn to enjoy fish!
OMG, so very delicious, absolutely loved this recipe!!!! And so easy to make. Will become one of my go to recipes.
I’m new to cooking fish. This was delicious! I didn’t have any Cayenne but we loved it.
I love this recipe! It’s easy and tasty when cooked right! 😂 that’s my problem… I even used a thermometer and still I overcooked it. I need help desperately. Any hints in cooking the fish?
Glad you’re loving it! The most important tip is to be sure frozen fish is fully thawed in the refrigerator for 24 hours or more. If it’s icy in the middle, it will cook unevenly. According to the FDA, fish should be cooked to an internal temperature of 145 degrees F, but many find that to be too much. For the best resut, try removing the skillet from the heat once the thickest portion of the fish is about 135 to 140 degrees F. The fish should be well browned with a tender, flaky interior. Here’s an article you might find helpful – Internatal Temperature Guide for Cooking Wild Fish.
Thank you so much for your response. I’ll keep on trying until I get my perfect blackened Mahi!!!
It was fantastic one of my all time favorites
This turned out amazing! I paired it with roast root vegetables.