Blackened Mahi Mahi

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!

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.

Sign up for my free newsletter for all the latest recipes and join me on Facebook, Instagram and Pinterest for more cooking inspiration!

Blackened Mahi Mahi

4.96 from 289 votes

You can easily control the level of spiciness in blackened fish by making your own Cajun spice mix. This is a super fast, incredibly delicious way to add more seafood to your diet.

Course: Main Course

Cuisine: Cajun

Author: Valerie Brunmeier

Keyword: blackened mahi mahi

Print Recipe Pin Recipe Rate Recipe

Prep Time:10 minutes minutes

Cook Time:8 minutes minutes

Total Time:18 minutes minutes

Servings: 4

1x2x3x

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

If you’re cooking more than 4 fillets or would like to add a more generous amount of seasoning, follow my recipe to prepare a big batch of Kickin’ Cajun Seasoning Mix.

Nutrition

Calories: 268 kcal · Carbohydrates: 4 g · Protein: 38 g · Fat: 11 g · Saturated Fat: 5 g · Cholesterol: 164 mg · Sodium: 540 mg · Fiber: 1 g · Sugar: 1 g

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.

Did You Make This?We love seeing what you’ve made! Tag us on social media at @fromvalerieskitchen for a chance to be featured

Love My Recipes? Get The Cookbook!

The Foolproof Family Slow Cooker and Other One-Pot Solutions