This Butter Poached Sous Vide Cod is one of those dishes that makes me feel like I’m eating in a fine-dining restaurant, but I’m actually just standing in my own kitchen in slippers. The fish comes out perfectly flaky and moist every single time, and the rich mushroom sauce spooned on top ties everything together. It’s the kind of recipe I pull out for date nights at home, but it’s simple enough that I’ve made it on a weeknight too, with broccoli steaming away on the side.

Why I Keep Coming Back to This Recipe
Cooking cod can be a little nerve-wracking — it goes from tender to dry in minutes if you’re not careful. That’s why I fell in love with the sous vide method for this dish. Once the fillets are sealed with butter and miso and placed in the water bath, I don’t have to hover nervously over the pan.
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Consistently Perfect Texture – The fish comes out buttery and flaky every time, never rubbery or dry.
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Butter Poached Flavor – Cooking it gently in butter infuses the fish with richness without overpowering its mild taste.
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Restaurant-Worthy Presentation – That silky mushroom sauce makes the whole plate look like something you’d order out.
Step by Step: My Way of Making It
Prep the Fish
Season the cod lightly with salt and let it sit for a bit. This firms up the texture and gives it a head start on flavor.
Make the Butter Paste
Mix softened butter with white miso paste. The miso brings a subtle sweetness and umami that balances the richness of the butter.
Seal and Cook
Place the fish in a vacuum-sealed bag with the butter paste and mirin. Lay the fillets in a single layer so they cook evenly. Into the 130°F water bath they go for 30 minutes.
Make the Mushroom Sauce
While the fish is cooking, sauté shiitake mushrooms. When the cod is done, pour the bag juices into the pan — that buttery liquid transforms the mushrooms into a velvety sauce. If it looks too thick, a little extra butter smooths it out.
Finish and Serve
Carefully remove the cod (it’s delicate!) and spoon the mushrooms and sauce over top. A sprinkle of fresh parsley or chives finishes it off beautifully.

My Personal Tips and Notes
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Same Thickness Matters – If one piece of cod is thick and another is thin, they’ll cook differently. Trim or pair fillets of similar size.
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Keep the Bag Down – I’ve had bags float in the water bath. Using a sous vide weight or even a spoon clipped to the side of the bag works like a charm.
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Frozen Cod Works Too – You don’t even have to thaw it first; just add another 15 minutes to the cooking time.
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Dried Mushrooms Trick – If fresh shiitakes aren’t available, rehydrated dried ones add an even deeper flavor. Just make sure to squeeze out extra water before slicing.
Make-Ahead Tips
You can season and seal the cod ahead of time, then refrigerate until you’re ready to cook. The mushroom sauce can also be made earlier in the day and gently reheated when you serve. That way, all you’re doing at dinnertime is cooking the fish in the water bath and assembling the plate.
Serving Ideas
This buttery cod feels indulgent but doesn’t weigh you down, so it pairs well with both rich and light sides. Some of my favorites:
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For comfort food mode: garlic mashed potatoes or creamy truffle risotto.
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For something crisp and fresh: steamed broccoli, sautéed spinach, or a simple green salad with lemon vinaigrette.
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For a full-on special occasion: start with sous vide lobster tails, serve the cod as the main, and finish with a light citrus dessert.
Storage
Leftovers keep well if handled gently. Store the cooked fish and sauce separately in airtight containers in the fridge for up to 2 days. To reheat, warm the cod slowly in a low oven or by slipping the sealed bag back into a warm water bath. The key is to avoid high heat so the fish stays tender.

FAQs
Do I need to salt the cod before cooking?
Yes, it helps firm up the texture and seasons the fish from within. A quick 30-minute rest with salt is enough.
Can I leave the skin on the cod?
You can, but since the fish cooks sealed in butter, I usually prefer skinless fillets for a cleaner presentation.
Do I need to sear the cod after sous vide?
Not for this recipe. The butter poach and mushroom sauce give plenty of flavor, and searing can make the fish fall apart since it’s so delicate.
Can I make this without miso?
Yes, though the miso really adds depth. A small splash of soy sauce or fish sauce can mimic some of that savory flavor.
What’s the best way to reheat it?
Gently! Either in a warm water bath or in the oven at a low temperature, covered with foil. Avoid microwaving as it can toughen the fish.
Butter Poached Sous Vide Cod
This butter-poached cod made with sous vide is tender, flaky, and full of flavor.
Ingredients
- fresh cod fillets
- unsalted butter, room temperature
- white miso paste
- shiitake mushrooms, sliced (fresh or rehydrated dried)
- garlic clove, minced
- mirin
- rice vinegar
- salt
Instructions
- Begin by lightly salting the cod fillets and letting them rest for 30 minutes. While the fish rests, stir together softened butter and miso paste until smooth.
- Set your sous vide water bath to 130°F (54°C). Place the cod, miso butter mixture, garlic, mirin, vinegar, and salt into a vacuum-seal bag, arranging the fillets in a single layer. Seal tightly, then submerge fully in the water bath. Cook for 30 minutes.
- While the fish cooks, prepare the mushroom sauce. If using dried shiitakes, soak them in hot water for about 30 minutes, then squeeze dry, discard stems, and slice. Heat a skillet over medium heat and sauté the mushrooms until tender.
- Remove the cod from the sous vide bag and set aside. Pour the cooking juices from the bag into the skillet with the mushrooms and simmer for 2–3 minutes, creating a rich sauce. If the sauce becomes too thick, melt in a little extra butter.
- Serve the cod fillets warm, spooning the mushroom sauce over the top. Enjoy with steamed rice or vegetables for a complete meal.
Nutrition Information
Yield
4Serving Size
1Amount Per Serving Calories 102Total Fat 4gSaturated Fat 2gTrans Fat 0gUnsaturated Fat 1gCholesterol 32mgSodium 340mgCarbohydrates 5gFiber 0gSugar 4gProtein 11g
Easy Shrimp Recipes.com, occasionally offers nutritional information for recipes contained on this site. This information is provided as a courtesy and is an estimate only. This information comes from online calculators. Although allchickenrecipes.com attempts to provide accurate nutritional information, these figures are only estimates.
Final Thought
Butter Poached Sous Vide Cod is the kind of dish that makes you slow down and savor every bite. The fish is tender, the sauce is luxurious, and the whole meal feels special without being fussy. It’s one of those recipes that reminds me why I love cooking at home — because sometimes the best dining experiences happen right at your own table.

