Fish & Shellfish

How To Cook Fish

Follow these few simple rules when selecting and cooking fish and you’ll serve up meals to be remembered.
There’s nothing tastier than fresh salmon so why not take the time to prepare and fillet your own. The end results are fantastic.

Fish has always been a healthy meal. Not to mention that it’s highly adaptable and versatile. You can cook fish using almost any type of cooking method: baking, grilling, steaming, frying or poaching. It’s really easy to prepare and there are endless options available to make awesome recipes out of it.

What we first need to do is learn how to tell when the fish is fresh and when it’s not:

  • Check the eyes: The eyes of the fish must be clear and bright. Dull-eyed fish may be safe to eat, but they are unlikely to be fresh.
  • The fish should look metallic, clean and shiny. If it’s discoloured, don’t buy it.
  • A fresh fish should smell like clean water, or a little briny. Don’t ever buy a bad-smelling fish.
  • When buying fillets, look for vibrant coloured flesh.
  • The scales should be tight and not flaking off.
  • The fish should be firm to the touch.

Remember to store the fish well. Good quality fresh fish should keep in your fridge for 2-3 days – but it’s always better to eat on the day of purchase. Keep the fish in the coldest part of your fridge. Remove fish from any packaging a couple of hours before cooking and rinse well to remove any loose scales. Pat dry and leave in the fridge uncovered in an oven tray until cooking time.

No one likes a mouth full of bones. Your fishmonger will always fillet for you but if not, use a filleting knife and tweezers to remove all bones.


The most important tip when cooking fish is to be really careful not to overcook it. Whether you’re preparing a fillet, steak, or whole fish, overcooking it may (and probably will) result in dry and tasteless meat. The “10 minute rule” establishes that fish should be cooked 10 minutes for each centimetre of thickness apart from when deep-frying or microwaving.

Seasoning the fish before cooking is important, so you may want to add a little ground black pepper and a sprinkling of herbs and spices. Put the top on the steamer and leave it to cook. If you choose to steam the fish, you can do so by filling the bottom of a saucepan with 2 cups of water, herbs of your choice e.g. parsley stalks and a slice of lemon with the fish in on top of it.

To pan fry fillets just dip the fish in seasoned flour before cooking in Stork Margarine for 5 minutes per every centimetre of thickness. Most people like the skin to be a little crispy so fry skin side down. Add the fish to the pan, skin side down. The fillet will immediately contract, and curve upwards. 

When this happens, the skin is only in contact on the outside edges. Take a bendy spatula and press on the flesh for a couple of seconds until the fillet flattens out. This ensures the skin remains touching the pan and produces nice crisp, evenly cooked skin. Don’t play with the fish or flip it back and forth, just turn once, towards the end of cooking. Once it starts to flake, it’s ready.

Tuna is a different. Use a very hot pan and only sear the outside of the fish.

The middle should be a nice reddish pink colour.

For perfect cod in parsley sauce, make a roux, gradually add in some milk, stirring all the time. Add in a Knorr Vegetable Stock Pot, some cream and bring to a gentle simmer. Add the cod fillets and poach them gently in the sauce for 6-7 minutes, turning just once after about 5 minutes. Add some chopped parsley to serve.

A nicely grilled sea bass or red snapper is always a treat. Remember to cut some strips into the skin before cooking. You can rub with a little salt and some olive oil or for extra flavour try heating a little olive oil on very gentle heat. Add a Knorr Vegetable Stock Pot and stir until the stock melts. Remove from heat and leave to cool for 5 minutes. Then rub the stock mixture into the skin of the fish before cooking. The fish can be stuffed with lemon, garlic and your choice of herbs and is great fried with some tomatoes and chillies and served with some fresh basil leaves and stuffed olives. Grill for around 7-8 minutes each side depending on the size of the fish and serve immediately.

For an example of how to cook fish as part of an entire meal, take a look at our recipe for Delicious Oven-Baked Fish and Chips. This is a subtle variation on a family favourite that uses lemon rind, lemon juice and paprika to create a simple and tasty dish.

Use a Knorr Chicken and Mushroom Pan Dry Cook-in-Sauce to enhance citrus flavours, before rubbing over the fish and baking. Serve with crispy potato wedges for a truly satisfying meal.