How to Cook Perfect Fish, Every Time

Cooking fish can be deceptively tricky. When you think it’s going to be a simple, delicious weeknight dinner, your fillet comes out overdone—but don’t be disheartened! The key to avoiding the most commonly made mistakes when cooking fish, is as always, knowledge and practice! Just as with cooking meat, timing, type and preparation are key. Here are our top tips for preparing different types of fish.

What do you find the most challenging about cooking with fish? Is there a mistake we missed?

1. Choosing the right fish

Just like cuts of beef, pork, or chicken, some types and cuts of fish are more suited to certain preparations. Those that are tough and lean make an ideal match for stews, while the marbled and tender ones are better when cooked quicker.

A fish stew or stock would do well with a firm, mild flavored fish like halibut, snapper, or cod that can withstand long cook times without turning to a mush or overpowering the dish. Oily fish like tuna, salmon and mackerel do better with a shorter cook time which will allow the delicate texture and natural fats of the fish to shine through. If you’re working with a less common fish, ask your fishmonger for their recommendation for preparation. When possible, look to purchase local, high quality fish and seafood.

2. Fresh or frozen?

Fresh fish should ideally be used the day it is bought or within a few days of purchase, kept refrigerated. It will smell lightly of the sea, but never have a strong fishy odor. If purchasing a whole fish, you’ll know it’s fresh if the eyes are concave rather than flat and the scales shiny rather than dull.

Depending on your location and access to fresh fish, frozen might just be the best option for you. If you’re going frozen, always look for flash frozen. This method helps preserve moisture while minimizing shrinkage when the fish thaws. Look for fattier fish like trout or arctic char if you want to buy frozen as they withstand the process better than a delicate white fish like cod or haddock.

3. Wrong tools for the job

Whether you’re grilling, baking, frying, or sautéing, fish is a delicate protein, so before you lose half of it through a grill grate or onto the floor, choose your tools wisely. Opt for a spatula or flipper rather than a set of tongs, as they can more easily tear the tender flesh. A grill basket is great for whole fish on the grill or, in a pinch, you can wrap your fish in aluminium to keep it safe and moist over flame. These methods also keep the fish intact and will help prevent breakage through the grill.

Baking “en papillote”—a French technique of wrapping and cooking food in parchment paper—is a healthy method for locking in moisture and effectively steaming fish. Try this recipe for Salmon and Vegetables in parchment to test it out for yourself.

4. Prep yourself

A whole fish is nothing to be afraid of— learn how to fillet a fish yourself in our tutorial below which walks you through step by step. Once your fillet is ready (either by your own work or the work of the fishmonger), it needs to be at an even, room temperature and have a dry surface if you want achieve a sear or crispy skin. This means taking fish out of the refrigerator approx. 20 minutes before cooking and never cooking with frozen fish—always thaw it first! Then, pat the room temperature fish on both sides with a paper towel before cooking to ensure a dry surface. When the fish is dry sears as soon as it hits the pan, rather than steaming.

5. Know when it’s done

Again, each fish is unique, and much depends on its size and the method by which you’re cooking, so familiarize yourself with ideal internal temperatures and cook times for your favorite types and cuts of fish. The two simplest ways to know when a fish is cooked are by sight: fish flesh changes from translucent to opaque as it cooks, and the texture goes from quite firm to tender and flaky. Check the thickest part of the fish for level of doneness, and use an instant read thermometer if you’re unsure whether the fish is cooked enough.