Looking for a perfect cooked fish? This lemon butter swai is cooked to perfection using sous vide method. The fish is moist and tender, loaded with flavors.

Have you ever heard of “SWAI fish”? Swai fish is a catfish from Vietnam, which has a delicate texture and much milder taste than catfish which sometimes can have a “muddy” flavor.

Swai are moist, soft, flaky, and delicate and its flesh turns from lightly beige to whitish color once cooked. I have baked, steamed and now sous vide. You mainly can cook it anyway you like, because of its delicate texture grilling might be a bit challenging, as the fish might fall apart easily.

Apparently there was a “catfish wars” between US catfish farmers and Vietnamese farmers, many accusations were made about the swai fish being raised in polluted waters therefore being poisonous.
With all this said, I personally do not believe that US will allow untested products into the Country…therefore I believe that swai fish if safe for human consumption. I have bought swai fish at Costco and Trader Joe’s, and cook them occasionally. In my opinion, everything should be eaten in moderation, regardless of its beneficial claims as throughout time we have seen many products which were considered bad to good and vice-versa.

Okay, now that I told you a little about swai fish, let’s go to the recipe…again, the main cooking was done by using sous vide method, therefore very simple and straightforward. My sous vide cylinder, which I love it is from Anova and you can find it HERE.


  • 2 swai fish fillets
  • Salt and pepper to taste
  • ½ tablespoon olive oil
  • 2 tablespoons butter
  • 3 tablespoons freshly squeezed lemon juice
  • 1 teaspoon lemon zest
  • Parsley for garnish


Preheat water oven to 56°C.

Rinse the swai fillets and pat them dry with paper towels, cut into half. Sprinkle salt and pepper on both sides of the fish. Place the swai into a 1 gallon freezer quality plastic bag.

To create a vacuum in the bag, carefully place the bag with fish fillets into the water-bath, make sure to immerse the bag until near the seal, this will create a vacuum, then seal the bag. I usually seal the bag leaving approximately 1 inch open and then immerse the bag until near the seal and finish by sealing the remaining 1 inch.

Cook for 30 minutes. Once the cooking time is off, remove the fish filet carefully as they break easily and place them in a plate.

In a small pan add the butter, lemon juice and lemon zest. Heat under medium heat until the butter is melted and starts to brown a little. Remove from the heat and pour over the swai fish. Garnish with parsley before serving. Serve hot.

Did you know that swai fish in spite of being from the catfish family is also called iridescent shark due to its resemblance to shark? Moreover, they are fresh water fish found naturally in Mekong River and Chao Phraya River, Vietnam.

Thank you for visiting Color Your Recipes…have a colorful week!