Published March 1, 2012. From Cook's Illustrated.
Restaurants have an unusual technique for turning out supremely moist, tender fish fillets.
Poaching delicate fish fillets may work in a restaurant, but it can be a greasy recipe for disaster when prepared at home.
We wanted to get light and moist poached fish using as little oil as possible.
Our first decision was to go with skinless fillets since the oil would never get hot enough to crisp the skin. We settled on cod for its firm, meaty flesh and clean flavor.
After a few preliminary tests, we realized that it wasn’t necessary to fully immerse the fish in oil. Instead, we poured enough oil into the pan to come roughly halfway up the sides of the fish and brought the oil up to temperature. But with relatively little oil in the pan, we had to constantly fiddle with the burner knob to keep the oil from getting too hot or too cold. We needed a steadier, less-direct heat source. Our oven fit the bill.
Our plan was to heat the oil on the stovetop to well above our target temperature and then rely on the oven’s more-even heat to keep it in the poaching sweet spot. But before we added the fish, we had another idea: Why not use this hot oil to lightly fry a garnish that could serve as a textural contrast to the silky fish? We defrosted a bag of artichoke hearts, patted them dry, and halved them lengthwise before tossing them with cornstarch and dropping them into the shimmering oil with some minced garlic. To decrease the amount of time we had to wait for the oil to come down to poaching temperature after frying the artichokes, we used only some of the oil; the other bit we left at room temperature and added to the pan after the garnish was done cooking, which sped up the cooling. A few minutes after frying, the oil was cool enough for poaching.
Frying up a garnish had also left us with an added bonus: flavor-infused oil to use for the sauce. After the fish was done cooking, we poured some of the oil into the blender and whirred it with cherry tomatoes, sherry vinegar, and some shallot. After a quick spin and a pass through a fine-mesh strainer, we had a silky-smooth vinaigrette.list of recipes