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!
This recipe is definitely a keeper! We have fixed this several times and it never disappoints. It goes so well with sweet potatoes. Simple flavors with enough spice to liven it up.
Made this recipe for my wife and she loves it. A few weeks later we went to a well-known restaurant in the area that is known for their blackened mahi. After she finished it she looked at me and said mine was the best she has ever had. Thank you very much for the recipe.
Oh, this is so great! Thanks so much for your comment, Randy. 🙂
Amazing! Just made this for the first time. Thank you!
1st time having Mahi Mahi, loved it!! I used a blackened spice bit i think next time I would make my own and minus the salt win win for us!!
That is exactly why I started making my own. Once you do, there’s no going back! Thanks for your comment, Diana 🙂
I’ve made this recipe a few times now. I have tried it with the Mahi Mahi but it isn’t my favorite fish so tried last night with halibut and wow! So delicious. The flavour of the rub worked so well with the halibut. Thank you for this recipe. Definitely a keeper in our rotation.
I would give this 10 stars if I could. I don’t like spicy so I just eliminated one of the hotter spices. Amazing! Thank you so much for this.
Loved this recipe and then tried it with salmon- awesome!! We aren’t fans but “force “ ourselves to eat salmon for health reasons . We really enjoyed this!
Consider baking the sweet potatoes instead of steaming, it concentrates the taste. My family eats a lot of sweet potatoes. Steaming is faster and you can peal and cut them in pieces, but nothing like the taste of a baked one. It likely will take 60 to 90 mins to bake and it is impossible to over bake them, as they just get better when a little burned, carmelizing their sugars.
Yes, we love baked sweet potatoes! I wrote a post about that very subject on Wholesome Made Easy – Perfect Baked Sweet Potatoes. Thanks, Mike.
I’ve made this recipe as written, and I’ve also brushed it with oil, coated it in the spice mixture, then air fried it. I gotta say, the husband and I both agree it was MUCH better in the air fryer! Spice mix has great flavor either way though!
How long did you air fry it?
That’s funny. I have been using that blend of spices less the thyme for years. And just a suggestion. Brush the fish with olive oil and you can get more of the spices to stick . Otherwise, it was awesome!
I just tried this tonight and this seasoning combination was fya! I am always wary of online chefs and the lack of seasoning and taste in their recipes, but this one was really good. It was just the right of “kick” and not overpowering or spicy. My picky son liked it, which is always a good thing.
I’ll be adding this to my recipe file for sure!
I love the simplicity and flavor of this recipe. The flavoring was perfect and yielded very moist fish. I did not have onion powder and the recipe still came out delish. This recipe is a definite keeper for me! Thank you.