Some things automatically go against the grain. Dumping two bottles of half decent olive oil in to a pan, and then loading it up with fish and herbs for instance. However, 20 minutes later and it all becomes understandable. Tender, flaky moist fish with such a delicate flavor and texture. If you get it right, the fish just quivers as you carry the plate to the table. This to me is the very exciting sign of a perfectly cooked piece of fish. It can seem like you don’t even need to touch it with a fork, merely just get it close, to see it flake in to pieces. Each bite yields perfectly cooked fish throughout, with subtle flavors pulled from the oil and herbs.
I first started cooking fish this way a couple of years ago and haven’t stopped since – especially in the summer since this yields light, but rich fish. Originally it seems like an extravagant preparation, requiring a lot of oil that will no doubt get junked after cooking. Screw it up, and you waste a good job lot of olive oil, and some lovely pieces of fish. Get it right and you would be hard pushed to find such an intricately flavored piece of fish. Thankfully, it really isn’t hard to do – a careful eye and an instant read thermometer (or a fancy candy thermometer) and you are set.
Whilst some cooking methods can easily remove moisture from food (roasting for one), cooking fish in oil doesn’t. If you keep the temperature low enough the oil almost seems to add to the richness of some fish (cod in particular), and provides a delicate fruitiness to the taste of the fish flesh.
Oil poached fish is great paired with simple summer vegetables. A little beet salad, some leafy greens and you are away. Some grilled zucchini and some freshly made hummus is also a favorite pairing of mine at the moment (more on those bad-boys later..) If you find the fish too rich, top with some simple pickled carrots or onions (or anything). Why not flake the fish up, mix with some cooked beans (or chickpeas) and a little arugula? Dress with sherry vinegar and some oil from the poaching – not forgetting salt and pepper and you have a great fish salad.
Did I mention that fish prepared this way is great cold too? I oil poached some local albacore tuna like this last week (which is incidentally the photo above – a quick snap whilst cooking) to have as an office lunch, along with a lovely French lentil salad.
The biggest key to success in oil poaching fish is controlling the temperature. You want the oil to be at a temperature of about 120F. Anything above 135F and you start to get towards overcooking and drying out the fish. Gentle and slow are the rules here. Now, I have a gas range and even on my simmer burner it is hard to keep a temp that low. The best thing to do is to be watchful, and pull the pan from the heat for a few minutes, and then put it back on as the temp goes down to, say 115F. A piece of fish about 1.5 inches thick is going to take 15 or so minutes to cook at this rate.
What fish can you oil poach? Quite a lot really. I like to poach fish fillets that have good thickness to them. Here in the Pacific Northwest, local albacore is fantastic like this. Salmon is delicious this way too. This turns something as neutral as true cod into a complexly flavored perfectly cooked piece of fish. Black Cod (Sablefish) is great this way too. You could even then take the Black Cod and crisp up it’s skin in a separate skillet once poached (careful not to overcook the fish though).
Top tips for oil poaching fish:
- Pick fresh fish, with a good thickness to the fillet for the most rewarding oil poached fish. 1.5″ to 2″ fillet thickness is a good bet.
- Use a good quality oil, but not something expensive and amazing since you will be using a lot of it.
- It is easiest to poach fish with skin on. This helps them keep together.
- If you don’t have enough oil in your pan, and the top of your fish is sticking out.. Don’t fret, every so often spoon some of the warm oil over. Half way through cooking, gently roll the fish over so that top is now bottom.
- Use an instant read thermometer or candy thermometer to keep a close watch on oil temperature. 120F is perfect.
- The fastest way to cool the oil down if it gets too hot is to remove the pan from the heat.
- The easiest way to control the heat is also to move the pan on and off the heat, being careful as you do.
- The fish can be kept off the heat, in the warm oil for a few minutes whilst you finish the rest of a dish you are making.
- Flavor the oil with fresh herbs if you wish – details below!
- If you are flavoring the oil with herbs, heat them in this oil until about 160F. Let this sit for 20minutes to infuse, then cook the fish in it.
Oil poached fish recipe:
8-10oz fresh fish fillet (see fish species advice above)
4-6 cups of decent enough olive oil
sea salt to taste (a good pinch)
4 bulbs of garlic
herbs of choice – rosemary, thyme, savory, oregano are all good choices
1) if you are using herbs – put the oil in a pan, big enough to hold the oil and the fish. The smaller the pan, the less oil you have to use. Put the herbs in the oil, along with a pinch of salt.
2) Heat the oil up till pretty hot – say 180F. Remove from the heat, and let cool back down to 120F or lower – say 30minutes. This steeps the herbs in oil, adding flavor to it.
3) Pat the fish fillet dry. Cut in to two pieces.
4) Heat the oil gently until it reaches 120F. Check with an instant read thermometer or candy thermometer.
5) Gently add the fish to the oil.
6) Keep the heat of the pan around 120F – move the pan on and off the heat as required to maintain a consistent temperature.
7) Depending on the thickness of the fish, they might take about 15 to 20 minutes to cook through.
Test the fish by taking a piece out and trying to flake it with a fork. It should flake easily, and be just opaque all the way through.