A super simple blackened fish taco recipe served with a creamy avocado lime sauce to drizzle on top. Firm white fish is coated with a spicy seasoning blend and pan-fried until lightly charred on the surface for maximum flavor.
This fish taco recipe is inspired by a food adventure just south of the border in Baja California, Mexico. My husband and I stopped at several small seaside villages like Puerto Nuevo for langosta (lobster) and pescado (fish).
The food in Baja is incredible. Street cart vendors selling elotes and tacos al pastor, carnitas, carne asada, lengua, and most restaurants have whatever your heart desires.
This recipe uses a Mexican-inspired spice blend that works with any type of fresh fish. This time I choose to Mahi Mahi for its lean flakey texture, which is a match made in heaven rolled up in a corn tortilla and all the taco fixings. Taco Tuesday is never going to the be the same from here on out!
The best ingredients to use for the blackening seasoning
The best blackening season combines smoked paprika, brown sugar, garlic, onion, cumin, chili powder, salt, and black pepper. It layers on a flavor explosion that takes a mild white fish to bold and rustic in taste.
If you want more heat, just add more chili pepper, or better yet, some cayenne pepper. If you’re following a Paleo or Whole30 diet, you can omit the brown sugar. The sweetness is there to balance the savory seasonings and helps to brown the surface more quickly.
How to make blackened fish tacos
- Blend together sour cream, water, avocado, cilantro, lime juice and zest, and serrano pepper until smooth.
- In a small bowl combine paprika, brown sugar, garlic powder, onion powder, cumin, chili pepper, salt, and pepper.
- Generously season both sides of the fish with the spice blend.
- Heat oil in a large skillet over medium-high heat.
- Add fish fillets and cook 2 to 3 minutes on each side.
- Serve fish pieces with flour or corn tortillas and avocado lime sauce.
Mahi Mahi only requires a few minutes to cook before it gets dried out, so keep an eye on it. Start with a nice hot pan by pre-heating over medium-high heat for a few minutes until you can feel the heat rising. I use a cast iron skillet, however, stainless steel or nonstick pan will work too.
Press the fish against the pan
Add enough oil to coat the bottom of the pan, and then heat until almost smoking. Carefully add the fish and gently press on the fillet with a spatula for a few seconds so the flesh can make direct contact with the hot pan.
This also helps release some of the moisture from the surface of the fish so the meat can brown evenly. Flip the fish and finish cooking. This process takes about 5 to 6 minutes max.
Avocado lime sauce
A quick avocado lime sauce can be made using a blender to create a smooth and creaming topping. It’s a simple combination of sour cream, ripe avocado, cilantro leaves, fresh lime juice and zest, and serrano peppers.
Crema or plain Greek yogurt can be substituted for the sour cream. Any type of pepper can be used, just adjust the amount to your heat tolerance, this sauce is mild. The fresh, tart and creamy sauce cools down the spices the on the fish for a tasty pairing.
Additional toppings for fish tacos
- Pico de gallo
- Mango Salsa
- Guacamole
- Lime wedge to squeeze on top
- Shredded cabbage- Green or red
- Crema- A mild Mexican white sauce similar to sour cream
More Mexican recipes
If you make this recipe, please let me know! Leave a comment, rate it, and don’t forget to tag a photo #jessicagavin on Instagram. I’d love to see what you come up with. Cheers, friends!
Why do you add brown sugar to the blackening seasoning?
The sugar not only adds a sweet molasses flavor but also speeds up browning on the surface of the mahi mahi. The desirable brown pigments appear at around 200°F (93°C) when the fructose in the brown sugar caramelizes to create a beautiful quick crust.
Blackened Fish Tacos with Avocado Lime Sauce
Ingredients
Avocado Lime Sauce-
- 1/2 cup sour cream, (120ml)
- 1/4 cup water, (60ml)
- 1 avocado, medium sized and ripe
- 1/4 cup cilantro leaves, (4g) loosely packed
- 2 tablespoons lime juice, (30ml) fresh
- 1/2 teaspoon lime zest, about 1 lime
- 1/2 teaspoon minced serrano pepper, seeded
Blackened Mahi Mahi Tacos-
- 1 1/2 teaspoons smoked paprika, (3g)
- 1 1/2 teaspoons dark brown sugar, (5g)
- 1/2 teaspoon garlic powder, (1g)
- 1/2 teaspoon onion powder, (1g)
- 1/2 teaspoon kosher salt, (3g)
- 3/4 teaspoon cumin, (1g)
- 1/4 teaspoon chili powder
- 1/4 teaspoon black pepper
- 1 1/2 pounds Mahi Mahi filets, cut lengthwise into smaller pieces if needed
- 1 tablespoon vegetable oil
- 8 corn tortillas, 6-inch
- 8 lime wedges
- 1 cup tomatoes, diced
- 1 cup red cabbage, sliced thin
- 1 cup green cabbage, sliced thin
- cilantro, for garnish
Instructions
- Add sour cream, water, avocado, cilantro, lime juice, lime zest, and serrano pepper into a blender.
- Process until smooth, scraping down the sides as needed. Add more water as needed to achieve desired consistency. Transfer to a small bowl and refrigerate.
- Combine paprika, brown sugar, garlic powder, onion powder, salt, cumin, chili pepper and black pepper in a small bowl.
- Sprinkle seasoning evenly over both sides of the fish filets.
- Heat oil in a large cast-iron skillet or sauté pan over medium-high heat.
- Add fish to pan then cook 2 to 3 minutes on each side or until the desired degree of doneness. The surface will blacken in color quickly so keep a close eye on the fish.
- Warm tortillas according to package directions.
- Divide fish evenly among tortillas.
- Serve with lime wedges, tomatoes, cabbage, and cilantro.
Recipe Video
Notes
- Blackening seasoning blend makes 2 tablespoons plus 1 teaspoon (20g, 5/8 ounces).
- Avocado lime sauce makes
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Made these tonight and they were amazing! Hubby kept saying how yummy they were too, thanks I’ll be making them again!
Thank you so much Jamie! I’m so glad to hear that you enjoyed the recipe 🙂
Hi, How did you get the skin off the mahi mahi? Yours looks beautifu. I loved the recipe too. Very tasty and not difficult to cook especially when we are in a hurry.
Can I use tilapia instead of mahimahi?
Hi Chelsea! Yes, you can absolutely substitute tilapia for mahi mahi.
Can you leave out the brown sugar or do you think that would drastically change the flavoring of the fish?
Hi Lakshmi-You can leave out the brown sugar, you’ll just have a smokier and more savory flavoring. Since there is no sugar, there will be less caramelization on the surface.
This is the third time making them in 3 weeks (once substituted with chicken). Follow the recipe to a T. The best tacos we’ve not only ever made, but have ever had. Easy, healthy, delicious. Awesome recipe.
Hi Angela- This comment truly made my day, I’m still smiling! I’m so happy that you enjoy this recipe, great idea switching it up with chicken, I’ll have to try it too 🙂
Fish tacos are my favorite. I love the idea of using blackened fish.
Me too Eileen! I made the blackened fish last night just to top on a salad, super versatile!
My god Jessica, your blackened fish tacos were the bomb!!! So good and so easy to make. I had to share this with my family members, hope you don’t mind. I just know there going to love it. Please keep up the good work… you need to have your own TV cooking show! Thanks again for all your great recipes.
Hi Jeff! You just made my day even more awesome!!! There’s nothing better than hearing that someone amazing had success with your recipe, thank you 🙂 I’ll keep sharing recipes and hopefully someday I’ll make it to the big screen! I appreciate your support, happy cooking 🙂
Absolutely delicious recipe! Served this with a mango jicama slaw from Trader Joes! Thank you!
I’m so glad you enjoyed the recipe Claire! The mango jicama slaw sounds amazing! I love TJ for some quick and yummy meal additions 🙂
Thank you so much for this recipe! My favorite place for blackend mahi mahi tacos just closed and this sounds like it would taste so close or possibly better then the fish tacos I used to get there. Thank you again!! I’m so excited to make these for dinner!!!
Hi Carley! I’m so sorry that you’re favorite restaurant closed! Hopefully you can enjoy this recipe just as much, let me know how it goes!
I have a large piece of frozen mahi mahi (skin on) – would you cut into filets, skin, and cook in pieces? Or just cook the large piece and then cut after it is cooked?
Hi Stephanie! I would remove the skin and cut into smaller fillets and then cook them 🙂
Hi Jessica. My husband and I love these fish tacos! He was the one who found your website and made them for me. I was wondering if there is any way to thin out the sauce a little bit. I don’t want to change the taste, so I was hoping you had a good recommendation.
I’s so thrilled to hear that you and your husband enjoyed the tacos Angela! I would say you could add either a little bit of milk, more lime juice, or a combination of lime and water until you get your desired consistency. You could also add a little less avocado or use a light sour cream if it’s really thick. Let me know how it goes!
Hi are the calories listed for this dish for one taco?
Hi Cindy! Yes, one taco 🙂
Really tasty recipe! My husband said they’re the best fish tacos he’s ever had! …and he’s tried his fair share of them! I made a generous amount of the seasoning with less sugar and more chilli. Served with mango radish salsa. Delicious! The bonus was that this took me 20min to make.
Wow Priya, that is a huge compliment! I’m glad that adding more spices and less sugar still made them tasty. Fast and yummy is always good!
Made this last night with frozen mahi mahi from Trader Joe’s. I’ve never tried to cook blackened fish before, and your instructions were spot on. Turned out perfectly and my husband was super-impressed. We both loved it and I can’t wait to try it on chicken too! I’ve tried two of your recipes now and both were absolutely delicious. I think I’ll just stay on your site and try a new recipe each night. So many great recipe ideas to choose from!
Yay Patricia! I like to use the TJ mahi mahi as well. Thank you so much for making my recipes, you made my day with your lovely comment. Let me know what else you try!
Can I substitute the Serrano pepper for a jalapeño or haberno pepper? Just use less perhaps? Looking forward ro making these tonight.
Hi Kristina- Yes! The jalapeno pepper is actually not as hot as serranos, so you can substitute 1:1 and add more to taste. Habaneros are much hotter, so I would use less and then add more if you want it spicier.
I saved this recipe months ago but last night was the first time to try it – what have I been waiting for?!!! It was delicious! I substituted some jalapeno for the serrano pepper (because that was what I had) but otherwise followed the recipe. Your short video is very nicely done too! The fish came out perfectly done and so tasty, and the sauce is perfect! Living in FL we miss the authentic So Cal fish tacos but no worries now, this recipe is even better! Thank you!
Can I use light brown sugar?
Hi Lissete- Yes, you can use light brown sugar. Thanks!
So yummy! Thank you!
You’re welcome Liliya!
Wow, Thank you for this amazing recipe. I made these Blackened Fish Tacos for my wife yesterday, and I have to admit these are some of the best fish tacos I ever tasted (my wife agrees!) Simplicity make this recipe a rarity; easy to prepare, flavourful, and fresh. This recipe is going into my standard rotation.
Thanks again.
You’re welcome Michael! So happy to hear that the family enjoyed the recipe and that it will become part of the rotation 🙂
This is now going to be a staple recipe in our house! The seasoning for the fish was excellent and the avocado cream sauce was to die for!
My husband loves fish tacos and this recipe will be my first try making them so I’m super excited to surprise him. We love crispy seared skin on fish, does this recipe still work if I leave the skin on the filets?
Hi Angie! Yes, if you like crispy skin, you can leave it on. You may want to add another minute or so to the skin side and only add the seasoning to the flesh side so the skin does not become too charred.
Can I substitute shrimp in this recipe?
Yes, you can substitute shrimp for the mahi mahi 🙂
would all your recipes be considered healthy/losing weight diet friendly?
Hi Jake- I have a variety of recipes, and enjoy using wholesome ingredients. Many of the recipes can be modified to suit your dietary needs. If you have specific questions, please don’t hesitate to ask!
How long does the avacodo lime sauce keep for?
I would say 2 days in an airtight container, put some plastic wrap between so the sauce has let exposure to air.
Wow! That was wonderful even my pre-teen boys ate it.
These were so good! I have been teaching my son to cook and when I said this is for dinner he was excited. They were amazing!
I love that you are teaching your son how to cook! Now he can make this dish next time 🙂
Great recipe! I did sub Mexican crema for the sour cream. You are right about the Avocado sauce. It will darken unless you keep it airtight. I thought about adding some more lime juice to prevent that, but I thought it would change the flavor.
I posted this on my IG feed, and I thought I’d leave you a message here!
Thank you for your feedback John!
This is a great recipe. I really love it. Easy after work dinner. I am from Texas and the spices are just right. Although for certain friends, I might kick it up a bit with more serrano peppers or jalepenos. instead.
Thank you for your feedback! Yes, feel free to add more spicy heat to your liking.
I went over the recipe three times, and I don’t see where or what you did with the avocado sauce.. I am not a stupid cook at 80 young but not specified.
I’m 17 and love to cook this are great recipes to start on. I’m going to Johnson and wales University in Miami.
Wow! These were so great! My whole family loved them. A definite keeper recipe! Thanks!
Hi! Would Ono fish work for this recipe?
Yes, I think ono would work for the fish tacos.
This was delicious! I also used Trader Joe’s frozen defrosted Mahi. I substituted jalapeno for the serrano as I couldn’t find any serrano locally. I used Swerve Brown Sugar (sugar-free) and it worked great. I love the dry rub and plan to use it on salmon and chicken. Who knows what else. My husband is not a Mahi fan but this may have converted him 🙂 Thanks for sharing!
These were delicious! I also used the Trader Joe frozen Mahi (defrosted). I used Swerve Brown sugar (unsweetened sugar) and it worked great. Also substituted jalapeno for the serrano. Love the spice mixture! This recipe may have converted my spouse into a Mahi fan 🙂
Used my homemade blackening seasoning and added cumin which worked great. Your Crema is delicious but I swapped out yogurt and kefir for the sour cream. This is the first recipe of yours that I have made, twice now. It is very tasty and healthy and I am looking forward to trying more.
Hey Jessica! Would I be able to make this by baking the fish instead of pan frying?
Can i substitute brown cane sugar for brown sugar?
Hello!
First time making these delicious fish tacos but definitely won’t be the last!
I thought it was going to be a lot harder but it was so quick and easy, it will be a regular on taco Tuesday!
Thank you so much!
Lisa
My husband and I made this together the other night and substituted a plant-based dairy-free sour cream in the sauce. I have to say that the caramelization on the fish from the brown sugar and the brightness of the crema sauce are SO complimentary! Hubby requested that we put this meal on our regular rotation. p.s. ask the fish counter to remove the skin from the fish to save time!
Great tip on getting the fishmonger to help clean the fish! So happy that you guys enjoyed the recipe.
This was definately a good recipie base. I made some changes that really made it pop mainly to the sauce. Instead of chili powder I used ancho chili powder. On the sauce instead of water I used heavy cream and added garlic salt to it. Then I used a hand blender to make the sauce creamy. Nothing but rave reviews from every one in attendance.