Sous Vide Cod (Butter Poached Cod)

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If you love butter poached cod, you’ll love this Sous Vide Cod recipe! This tender, flaky and buttery cod takes just 30 minutes to cook in a sous vide water bath and it’s served with the most amazing mushroom sauce.

It’s perfect for date night or an everyday meal!

While cod is an easy fish to cook, it’s also a fish that can be easily overcooked. That’s why I prefer cooking it using the sous vide method. It might take a little longer, but the controlled temperature of the water bath ensures the cod fillets are perfectly cooked and never dry or rubbery!

Don’t get me wrong, I love cod prepared in all different ways! On the grill, baked in the oven or seared in a hot skillet. In fact, pan frying cod is how we make these pesto cod fish tacos all the time! 

But, to ensure flaky and moist fish every time, there’s no better way to cook it than the sous vide! This sous vide tuna, sous vide mahi mahi, sous vide halibut and sous vide salmon have quickly become some of our favorite seafood recipes because of how perfectly they turn out using the sous vide method.

Using a sous vide just takes the guesswork out of cooking fish and you don’t need to keep a close eye on it either!

This gives me plenty of time to make some side dishes like these truffled mashed potatoes and this Instant Pot broccoli. Both are perfect with this buttery cod recipe!

Check out the sous vide cod story!

What is Sous Vide?

Sous vide is basically a method of cooking using what is called an immersion circulator. This immersion circulator circulates water in a temperature controlled water bath at a certain temperature to perfectly cook your food every time.

Because the temperature doesn't change, and it keeps your meat (or dessert, veggies, etc.) at the same temperature, your risk of overcooking becomes very minimal.

To learn even more about sous vide cooking, head over and read "what is sous vide cooking."

What is the Water Displacement Method?

The displacement method is where you slowly submerge a ziplock bag in water pushing the air out of the top of the bag (the bag should be slightly open at the top to allow air to escape).

Use a clip (I use binder clips) to clip the bag to the side to keep it from floating and getting air and/or water inside.

Tools Used

• Anova Precision Sous Vide Cooker
• 12 quart container
• Vacuum sealer
• Vacuum seal bags

Other sous vide recipes

• Sous Vide Swordfish
• Sous Vide Mashed Potatoes
• Sous Vide Risotto 
• Sous Vide Ribs
• Sous Vide Broccoli

Why this recipe works

1. The recipe is elegant enough for date night and easy enough for weeknight dinners! The butter poached flavor and melt-in-your-mouth texture make this cod dish impressive for any occasion!
2. Speaking of melt-in-your-mouth, that’s really made possible by using the sous vide. Just like poaching cod in butter, cooking the cod in a heated water bath infuses it with melted butter flavor and keeps the fish moist so it turns out tender and succulent!
3. The mild flavor of cod means it pairs well with a variety of different seasonings. That’s why we can get away with adding the umami flavor of white miso paste to this recipe. It makes the cod and the mushroom sauce both taste amazing!

What is cod fish?

Cod is a white, firm and flaky fish with a mild, slightly sweet flavor. It’s often compared to haddock, tilapia or even halibut. It can be farm-raised or wild-caught, with two varieties being Atlantic and Pacific cod.

Ingredients

Please refer to the recipe card below for a full list of ingredients and quantities.

You’ll need 4 cod fillets for this recipe. I used Pacific cod fillets with the skin removed.

The cod is cooked with 2 tablespoons of white miso paste. This is a type of miso where the soybeans are fermented with rice. It has a mild, sweet and umami flavor. 

The miso is mixed with 3 tablespoons of butter. Since the cod will be salted before cooking, you’ll want to use unsalted butter so the fish isn’t too salty. 

For additional flavor, you’ll need 1 tablespoon of mirin, which is a sweet Japanese rice wine. If you don’t have any mirin, you can try substituting dry sherry.

For the mushroom sauce, the recipe calls for 8 shiitake mushrooms (sliced). If you can’t find any, you can use dried shiitake mushrooms and soak them before using.

Step by step instructions

Heat a sous vide water bath to 130F degrees.

Salt the fish and let it sit for 30 minutes.

Mix together the butter and miso to make a paste.

Combine all the ingredients (except mushrooms) in a vacuum seal bag and seal.

Cook for 30 minutes.

Heat a skillet over medium heat and add the mushrooms.

Remove the fish from the bag and set aside. Add the bag juice to the mushrooms in the skillet and cook for 2-3 minutes.

**If the sauce is too thick, add some additional butter.

Spoon the mushroom sauce over the fish and serve.

Expert tips

1. To ensure the cod fillets cook evenly, make sure they’re all the same thickness. (The loin part of the fillet is usually thicker than the tail end).
2. If your fillets are thicker, you may need to increase the cooking time by about 15 minutes.
3. You’ll want to make sure the fillets are arranged in the sealable bag in a single layer. This will help them cook evenly.
4. For maximum flavor, make sure the butter is evenly distributed around the cod before the bag is sealed.
5. When sealing the bag, make sure the air is removed to avoid bacteria getting in the bag.
6. The sealed bag should also be completely submerged in the water bath. I like using something heavy like a sous vide sinker weight to prevent it from floating.
7. If the bag starts to float due to air getting in, just open the bag, remove the air and reseal it. 
8. Keep the bag juice (the juice from the bag the cod is cooked in) to make the mushroom sauce. If the sauce turns out too thick, just melt in some more butter.
9. You can substitute dried shiitake mushrooms if you can’t find any fresh. Just soak them in hot water for 30 minutes until they’re softened. Squeeze the excess water out, slice them and discard the stems. 

Common questions

Storage and reheating

Leftover cod and mushroom sauce can be stored together in an airtight container in the fridge for 3-4 days.

To reheat, place the cod and sauce in a shallow baking dish covered with foil and warm in the oven on 275F degrees until heated through. You can also reheat it in a covered skillet on the stovetop over low heat. 

Be careful not to reheat for too long as the cod may dry out and get tough and rubbery.  If the sauce has thickened or there isn’t much left, just add a little melted butter to the cod as it reheats.

Make it a meal

This buttery sous vide cod goes well with so many dishes! Here are a few ways we like to make it a full course meal!

• For an elegant meal, start with some sous vide lobster tail or go casual with some jalapeño hush puppies.
• In terms of side dishes, cod pairs nicely with black truffle risotto, garlic mashed potatoes or duck fat crispy smashed potatoes.
• For some extra veggies, we love Instant Pot Brussels sprouts, air fryer broccoli or Instant Pot carrots.
• And don’t forget dessert! For a dinner party, this sous vide cheesecake with strawberries is a great way to end the meal!

Did you make this recipe? Leave a comment below and let me know how it turned out!