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!
Used frozen Mahi Mahi fillets four each x 3 oz. Cut recipe for spices in half since it called for 4 each at 6 oz. fillets. They turned out great! I used chili powder for cayenne. I usually broil fish or grill it, but this was heavenly. Who doesn’t like fried fish?!?
I made the sweet potatoes with a bit of nonfat plain Greek yogurt, and they tasted like PIE to me. I’ve never made mashed sweet potatoes since i usually leave them whole. Life changing, and we are sooo full.
This was better than any Mahi I’ve ever had in a restaurant and so easy. Thanks for the great recipe.
Very tasty and easy. Loved it
Val, I scored some fresh, never frozen, mahi. Made an olive oil paste w/ the seasoning, dropping the oregano and increasing the thyme. Grilled up the fish, then on brioche buns with some shredded romaine and a dollop of mayo. Whoa Nellie. Major League Grand Slam !!!
That sounds amazing! Love what you did with it 🙂
The best fish we’ve ever made — even the 4 year old approved! This is going in the rotation
Just made this, and it’s a winner – very tasty and easy to make. We’ll cut back on the salt next time but otherwise it’s brilliant just as presented. Thanks!
This recipe sounds amazing and I think I made a similar one with sea bass bc I remember you blackened spice mix. Is it possible to roast or bake this mahi recipe?
I think you could definitely roast it but I haven’t tested that method. Let me know how it goes if you try it.
Amazing & Delicious! I substituted kosher salt because that’s what I cook with, dried basil instead of thyme because that’s what I had and on hand and subtituted a dash of cayenne because my husband doesn’t like spicy dishes. It came out perfect and I served it with mashed sweet potatoes like in the photos. What a great combination. I’ve been looking for a delicious mahi mahi recipe for years, and finally found it. This recipe will be one of our regular rotation of dishes. Valerie, Thank you for posting it!
This was amazing! I served it with brown rice and a mango salsa. My son thought it was spicy but loved the mango
Made this tonight for dinner with coconut jasmine rice and roasted broccoli. We all thought it was too salty, so next time I will half the salt. I also used 1/2 tsp of chipotle instead of cayenne. Winner in my house! This recipe is getting printed and put in my binder.
Oh my! Where has this been?! Very tasty and soooooo easy!
My husband and I loved this, except we’ll cut the salt way down next time. Thanks for a delicious new way to enjoy our mahi mahi!