Cooking seafood can be intimidating, but with a few simple rules you can avoid overcooked fish in favour of flaky, tender fillets. The next time you’re grocery shopping, let this guide on how to cook fish steer you in the right direction.
What to look for when buying fish
Use your sense of sight, touch and smell. Seafood should not have a pungent, fishy scent—this is an indicator the fish has gone bad. When buying whole fish, look for shiny scales that are tight to the skin and bright, clear eyes. When picking out smaller pieces, look for firm-to-the-touch fillets that are moist and hold together well (no gaping pieces). Temperature is key to maintaining the quality of the fish, so it should either be on ice at the fish counter or in a well-chilled area of your supermarket’s fridge or freezer section.
Should you buy fresh fish?
When buying meat, a fresh cut is the gold standard, but when it comes to fish, sometimes frozen is best. Vacuum-sealed fillets that have been flash-frozen immediately after harvest can maintain freshness better than fish at the seafood counter, which is often flash-frozen fish that has been thawed.
How to cook fish
An even cook is easy, with a few key tips. First, filets of different thicknesses won’t cook through evenly in the same amount of time, so keep an eye on the thinner fillets (they’ll cook faster). Second, cooking en papillote is a great technique to add to your repertoire — steam-cooking keeps fillets moist and adds beautiful aromatic flavour at the same time. Lastly, when baking or grilling fish, you’re looking for an opaque centre and just-able to flake finish. You can check doneness by temperature (158F), or sticking a paring knife into the thickest part of your fish; if, after a few seconds, the tip comes out warm (not hot) your fish should be cooked through.
This coldwater fish is extremely versatile. Cod’s firm flesh and mild taste make it excellent in everything from tacos to chowder. Look for moist, white-fleshed fillets from Pacific or Alaskan waters, and remove the skin before cooking for best results.
Best for: Stews, chowders, tacos
Haddock is a member of the cod family and shares its firm flesh and mild flavour profile. Its sturdy texture holds up well to batters and crumbs, making it a top choice for fish and chips. Haddock is slightly cheaper than cod, and can make a good stand-in.
Best for: Deep-frying, pan-frying, baking
Succulent, yet lean, halibut is commonly sold as steaks and fillets and is a pricier (albeit delicious) white fish option. Look for flesh that’s almost translucent, without a yellowish tinge. Halibut retains moisture well and is excellent baked, broiled, grilled or seared. Cook steaks skin-on in order to maintain their shape, and pair with fresh herbs, like parsley or basil, or capers, lemon or tomatoes. Look for wild Canadian halibut varieties, as American Atlantic populations are currently depleted.
Best For: Grilling, baking, ceviche
Tilapia is cheap and readily available, but has a reputation for being a less-tasty option because of its tendency to take on a muddy, earthy flavour. To make the most of this budget-friendly fish, seek out firm, pinkish-white fillets, and give it a boost with fresh herbs, lemon, lime, or spices. Catfish and flounder also make suitable substitutes in recipes calling for tilapia.
Best for: pan-frying, marinades
There are several varieties of snapper, but red snapper is the most popular and easily accessible. Considered one of the best-tasting white fish, snapper is firm, lean and particularly flavourful. Often sold whole, look for snapper with bright red gills as an indicator of freshness. When buying fillets they should have a slight red tinge.
Best for: Roasting or grilling whole
Red snapper recipe:
Farmed salmon, harvested from the Atlantic, is available year-round. You won’t see wild Atlantic salmon for sale—it’s an endangered species and cannot be fished commercially. Atlantic salmon tends to be flaky, buttery, and pale pink in colour, and is often sold as a skin-on whole side, fillet, or thicker cross-cut steak. Its sturdy texture makes it ideal for roasting—buy a whole side and you’ll easily have your dinner party main sorted.
Best for: Roasting, grilling, cooking on a cedar plank
Atlantic salmon recipe:
Wild Pacific salmon—also labelled as sockeye, Coho, or Chinook salmon—is leaner than its farmed counterpart, with a firmer, meatier texture and a deep coral pink colour from its crustacean-based diet. To avoid drying out leaner wild salmon, heat it to a slightly lower internal temperature (120 C instead of 125 C) during cooking.
Best for: Roasting, poaching, curing
Pacific salmon recipe:
Trout can easily be mistaken for salmon at the store due to the pink colour, however the taste profile can be very different. Freshwater rainbow trout is milder, while salmon has a bolder, sweeter taste. Steelhead trout (rainbow trout that has migrated to the ocean) is more similar to salmon and has a moderate amount of fat. Look for American or Canadian farmed rainbow or steelhead trout, which are a sustainable and relatively inexpensive choice. Avoid reheating leftovers (the fats will oxidize and give off an unpleasant odour!), and turn them into a tasty grain bowl instead.
Best for: A salmon stand-in, grilling, steaming
Ahi (or yellowfin) tuna is the variety you will typically come across at the supermarket, while pricier bluefin tuna is what’s used for sushi. Tuna has a savoury, meaty flavour and texture that is unique to the species, and is a great gateway fish for seafood newbies. Tuna’s skin is tough, so it’s typically sold in thick skinless steaks. When selecting tuna, avoid pieces that are uneven in colour, look dry, or have brown spots. Tuna is best served rare to medium rare, which preserves its bright pink colour and moisture content, and pairs well with Asian flavours, such as ginger, sesame, soy, and wasabi.
Best for: Grilling, pan-searing, sushi
Can you cook fish from frozen?
Thin, white fish, such as tilapia, sole, and haddock, yield equally good results when cooked directly from frozen. Firmer fish and thicker fillets like salmon, halibut and cod also cook well from frozen when properly thawed. Try to avoid purchasing frozen tuna and swordfish, they often end up dry and discoloured.
Farmed vs. wild fish
Fish farming can be sustainable and for some species, such as mussels, oysters and clams, farmed is actually preferable to wild-caught. Farmed shellfish is grown on hanging ropes in the ocean, which does little harm to the the environment, whereas dredging wild shellfish can damage the ocean floor. Environmental impact and the risk of toxins vary by species and region. Look for the Ocean Wise symbol—this indicates your food was produced sustainably, and search the Ocean Wise guide by species to learn which options the Canadian organization recommend.