How to Cook Fish Sous Vide: A Step-by-Step Guide

Sous vide is a cooking method that involves vacuum sealing food in a plastic pouch, then submerging it in a water bath held at a precise temperature. This results in food that is cooked evenly from edge to edge, retaining moisture and juices without overcooking. Fish is especially well suited for sous vide cooking, as it’s easy to overcook with other methods. The gentle heat helps ensure tender, flaky fish without drying it out. 

In this guide, we’ll walk through the process of cooking fish sous vide, from choosing the right fish to seasoning and finishing. With a few simple steps, you can achieve restaurant-quality fish at home.

1. Choose Your Fish

The beauty of sous vide cooking is that it works with most types of fish fillets and steaks. Good choices include:

  • Salmon: King salmon, sockeye, and Atlantic salmon fillets cook well with sous vide. The fish comes out moist and tender.
  • Cod: This white, flaky fish remains delicately flavored after sous vide cooking. Black cod (also called sablefish) is especially good.
  • Halibut: Steaks and fillets from this mild, meaty fish become juicy and tender with sous vide.
  • Tuna: For tuna steaks, sous vide helps ensure the interior is cooked through while leaving the meat rare.
  • Arctic Char: Similar to salmon, this fish becomes flaky, moist and flavorful with sous vide.
  • Bass: Sea bass, striped bass, and black bass fillets do great with sous vide cooking.

For best results, choose fresh fish and make sure it’s 1 to 2 inches thick for even cooking. Always start with high-quality fish from a trusted source.

2. Prepare Your Sous Vide Machine

To get started, you’ll need a sous vide immersion circulator or water bath setup. Attach the immersion circulator to a stock pot or large container filled with water.

Set the temperature on your sous vide machine to the desired doneness:

  • For rare to medium-rare fish: 104°F to 122°F (40°C to 50°C)
  • For medium fish: 129°F to 134°F (54°C to 57°C) 
  • For well-done fish: 140°F+ (60°C+)

Allow the water bath to come up to temperature before adding the fish. Make sure the container is large enough to hold the circulator and food without crowding.

3. Season the Fish

While the water is heating up, prepare the fish. Pat the fish dry and season both sides with salt and pepper. Go light on salty seasonings like soy sauce, as it can make the fish too salty when cooked sous vide. 

You can also rub spices and herbs like garlic powder, onion powder, paprika, thyme or dill on the fish to add flavor. Brushing with olive oil or butter helps the seasonings stick.

Don’t worry about over-seasoning, as sous vide cooking intensifies flavors. You can also marinate the fish beforehand to infuse lots of flavor.

4. Vacuum Seal the Fish

Next, seal the seasoned fish in a vacuum-seal cooking bag. Remove as much air as possible before sealing to ensure even cooking. 

You can also use zip-top freezer bags if you don’t have a vacuum sealer. Submerge the bag except for the zip-top part in the water bath, then seal while underwater to remove air. Clip the bag to the side of the container to keep it fully submerged.

5. Cook the Fish in the Sous Vide Machine

Gently lower the sealed fish bag into the preheated water bath. The thickness of the fish will determine the cooking time. In general:

  • 1-inch thick fillets or steaks: 45 minutes to 1 hour
  • 1.5- to 2-inches thick: 1 to 2 hours

For food safety when cooking fish sous vide, always cook for at least 45 minutes. Set a timer and verify the water bath maintains the set temperature during cooking.

6. Finish and Serve the Fish

Once done sous viding, the fish will be perfectly cooked edge to edge. Remove the bags and open carefully to prevent hot water from splashing out. 

For best flavor, you need to finish the fish by searing or grilling briefly to brown the exterior. Pat dry, then sear in oil or butter for 1-2 minutes per side.

The fish is now ready to serve! Flake gently with a fork and season again just before plating. Pair simply with rice, roasted potatoes or fresh vegetables. You’ll enjoy tender, restaurant-worthy fish easily at home.

Why is Sous Vide a Good Method for Cooking Fish?

Fish cooks quickly with exposure to heat, so it can soon become rubbery and dry using other cooking techniques. Sous vide’s gentle cooking process helps prevent overcooking. The vacuum-sealed bags also lock in moisture and flavor.

Cooking fish sous vide gives excellent results:

  • Fish comes out tender and juicy, even with lean types like cod, tilapia or bass.
  • The fish cooks evenly from edge to edge, eliminating dry spots. 
  • Flaky texture and delicate flavors are maintained.
  • Cooking below boiling temperature keeps fish from seizing up and drying out.

Sous vide machine’s precise temperature control means you can cook fish to the perfect level of doneness, from rare to medium-well. It takes the guesswork out of fish cookery.

What Types of Fish are Best for Sous Vide Cooking?

Most fish fillets and steaks do well with sous vide cooking. The ideal cuts are 1 to 2 inches thick. Good options include:

  • Salmon
  • Cod 
  • Sea bass
  • Mahi mahi
  • Halibut
  • Tuna
  • Trout
  • Arctic char
  • Snapper
  • Grouper

Lean fish like tilapia, sole and flounder also come out moist and tender with sous vide. Oilier fish like salmon and trout become exceptionally buttery and rich.

Thick fish steaks hold up well to sous vide cooking. Thinner fillets may become too delicate, so pad the bag to avoid folding the fillets. Supporting them helps prevent breaking.

What Temperature Should You Use for Sous Vide Fish?

With sous vide’s precise temperature control, you can cook fish to different levels of doneness by adjusting the temperature:

  • For raw or rare fish: 104°F to 122°F (40°C to 50°C)
  • For medium-rare fish: 129°F to 134°F (54°C to 57°C) 
  • For medium fish: 140°F to 144°F (60°C to 62°C)
  • For well-done fish: Above 150°F+ (65°C+)

Thicker cuts can be cooked at the lower end of each range, while thinner pieces do better at higher temps. 

For food safety, the FDA recommends cooking fish to an internal temperature of at least 145°F (63°C). With sous vide, cooking for an hour kills pathogens even at lower temperatures.

How Long Should You Cook Fish in a Sous Vide Machine?

Cooking time for sous vide fish depends on thickness:

  • 1-inch thick fillets or steaks: 45 minutes to 1 hour
  • 1.5 to 2-inches thick: 1 to 2 hours 

The minimum recommended time is 45 minutes for food safety. After reaching desired doneness, the fish can be held in the water bath for up to 4 hours without overcooking, letting you time servings to when you’re ready.

Temperatures between 122°F to 140°F (50°C to 60°C) provide the ideal texture for most fish. Cooking times longer than 2 hours start to make the flesh mushy. For best results, stick to shorter cooking times.

Can You Overcook Fish with Sous Vide?

It’s nearly impossible to overcook fish with a properly heated sous vide water bath. Since the water temperature is stabilized, the fish doesn’t keep cooking after reaching the target temperature. 

However, cooking fish for longer than needed (above 2 hours) can make the texture undesirably soft. For best results, stick to the recommended cooking times based on thickness.

You also need to avoid very lengthy cooking times above 160°F (71°C), which may start to dry the fish out. For well-done fish, just an hour or two above 150°F (66°C) gives the best texture.

What are Some Good Seasonings for Sous Vide Fish?

With sous vide’s gentle cooking, seasonings don’t burn or bake onto the surface like grilling or baking. The flavors infuse directly into the fish. Almost any herbs, spices, oils and marinades pair well with sous vide fish.

Some excellent seasonings to try:

  • Lemon, lime, garlic, parsley – classics for fish
  • Cajun or Creole seasoning 
  • Soy sauce, ginger, sesame oil, chili paste
  • Dill, basil, rosemary, thyme
  • Chipotle, paprika, cumin 
  • Teriyaki, barbecue sauce – use sparingly to avoid too much sweetness

Vacuum sealing locks in marinades excellently. You can also seal seasonings like fresh herbs, citrus slices or peppers in the bag.

What Sides Pair Well with Sous Vide Fish?

Sous vide fish comes out incredibly moist and tender. Simple side dishes work well to highlight its fresh flavors, without overcomplicating the meal:

  • Rice pilaf or risotto
  • Roasted or mashed potatoes
  • Roasted vegetables – asparagus, broccoli, Brussels sprouts
  • Green salad with vinaigrette 
  • Fresh bread or rolls

Lighter sides are preferable since the fish is the star. Cooked vegetables, pilafs and veggie noodle dishes also make good pairings.

The rich oils of salmon, tuna and trout can stand up to heartier sides like polenta, quinoa or barley. Enjoy your sous vide fish with creative pairings to complement its texture and flavors.