Just when you think you’ve cooked fish in every possible way, along comes an intriguing recipe like this one. This cooking method for seafood isn’t a new idea; the Italians and French have been doing it forever and many chefs today use it to keep fish moist while it cooks. But have you ever tried poaching fish in olive oil ?
It’s nothing like deep-frying and a whole different thing than poaching in water. Why do it? The fish cooks quickly, with less of a chance of drying out and the flavor of the fish stays pure and mild without turning fishy or becoming bland. The flavor of fish poached in olive oil is not oily, although you should use olive oil that you like the flavor of.
You should also choose fish with firm flesh like halibut, cod , salmon  or tuna (shrimp  can also be poached). Poaching in oil work best with small pieces of fish, both because the fish will cook quickly and because it allows you to use less oil. The thicker the pieces of fish are and the bigger the pot is, the more oil you’re going to need. Try to keep each piece of fish around 3 ounces, or even less by cutting the fish into small cubes.
Place the fish in a small pot or skillet and cover with olive oil. You can also add sprigs of herbs or cloves of garlic. Although they don’t add a whole lot of flavor to the fish, they do make the oil taste great. Turn the heat to medium-low and no higher. During the entire cooking process, the oil should be warm but not burning hot. You should be able to dip your finger in the oil and it won’t burn.
A 3-ounce piece of fish will cook in about 5-8 minutes, maybe a little bit longer, depending on how thick it is. When it’s done, the flesh should be moist, supple and pretty much melt in your mouth. The oil won’t have a fishy flavor. It can be strained and re-used for cooking or better yet, use it immediately to dress a salad or drizzle onto vegetables that you serve with the fish.
- Pieces of boneless, skinless fish (pieces that weigh 3-ounce/85 gram or less work best)
- Olive oil
- Optional: sprigs of herbs like thyme and rosemary and peeled cloves of garlic cut in half
Place the fish in a small pot or skillet. Lightly season with salt. Cover completely with olive oil. Add herbs or garlic if you’d like.
Set over medium-low heat. The oil should never get hot enough to boil and bubble, however, if bubbles start forming around the fish you’ll know it’s close or already done. Small chunks take around 5-8 minutes to cook. Tuna can take longer than other types of fish.
So as not to waste oil, use as small a pot as possible and/or cut the fish into small pieces.