Salt-crusting has all the drama of a restaurant technique, yet it's easy to do at home. In this recipe, the trout becomes ultramoist and tender during roasting and pairs nicely with the classic lemon-dill sauce.
Watch the Video Recipe to see the salt-crusting technique in action.
Position a rack in the center of the oven and heat the oven to 400°F.
Apply the salt crust
Tip:A gutted, scaled whole fish, with its head, is ideal for salt-crusting, but a headless fish works, too.
Rinse the fish well, inside and out. Make sure there are no loose scales on the skin. Pat the fish completely dry with paper towels and put it on a large rimmed baking sheet or cutting board.
Stuff the cavity of the trout with your choice of aromatics, if using. Rub the skin of the fish all over with the olive oil (this will make it easier to remove the salt crust after roasting).
In a large bowl with a rubber spatula, mix the salt with the egg whites and 1/4 cup plus 2 Tbs. water. Spread enough of the salt mixture on the bottom of a large rimmed baking sheet to make a bed about 1/4 inch thick and roughly the same size as the fish. Put the fish on top of the salt bed. Using your hands, coat the fish with the remaining salt mixture to make a 1/4-inch-thick crust, molding it around the contours of the fish. (If using a large fish, the tail or head may extend beyond the rim of the pan and therefore won’t be covered with the salt mixture—this is fine.)
Roast the trout
Cook the trout 40 to 45 minutes.
If using a remote probe thermometer, insert the probe near the spine behind the head (the thickest part of the fish). If using an instant-read thermometer, apply a marker (such as a piece of garlic or shallot) to the crust at this spot so you know where to check the temperature later.
Roast until the thermometer registers between 135°F and 140°F. Start checking at the lower end of the time range in the chart above. Let the fish rest in its crust for 5 to 10 minutes before serving.
Serve the fish
Tap the salt crust with the back of a large metal spoon to break it. Using a large fork and the spoon, push the crust to the side so the fish is exposed. Then use a pastry brush to flick away any salt that’s sticking to the skin.
With the spoon, gently scrape the skin off the top of the fillet and push it to the side. Run the spoon along the spine to separate the flesh from the bones. Use the fork to help move the flesh to serving plates.
Once you’ve removed all of the top fillet, grip the tail end of the bones and pull them away to expose the bottom fillet. Push aside any ingredients stuffed into the cavity. Use the spoon to separate the bottom fillet from the skin and lift the fillet onto serving plates with the fork or a fish spatula.
Photo: Scott Phillips