En papillote is a French cooking technique that steams food by enclosing it in parchment paper and heating it in a conventional oven. The method is most often used to prepare vegetables, fish, shellfish or boneless chicken breast. Liquid is often added to the package to flavor the food and create the steam.
Since steaming is such a delicate preparation process, the en papillote method typically works best on foods that cook quickly. To ensure even cooking, the items should be thinly sliced or chopped, yet sturdy enough to stand up to the heat of the steam. The food should also be receptive to absorbing tastes and flavors imparted by the liquid and herbs in the package.
Fish is generally considered the best food to cook en papillote based on its thinness and ability to quickly absorb the flavors of seasonings. The majority of recipes for fish en papillote recommend using a white, non-oily variety such as cod, snapper, sole, flounder, sea bass or pompano. The fish should be filleted, no more than an inch thick (about 2.5 cm) and uniform in size.
To prepare food by this method, cut a rectangular piece of parchment paper approximately three times the size of the food portion. Place the food in the center of the paper and place the seasonings on top. Julienned vegetables are frequently laid on top of the meat or fish at this point to add color and flavor. As if wrapping a package, fold half of the paper over the top of the food, do the same with the other half, and then crimp the edges to form a tight seal on all seams of the package. Some cooks staple the package closed, which works fine but can mar the appeal of the final presentation.
Right before the final seal is made, carefully pour the chosen liquid into the enclosure. Popular liquids include vegetable or chicken broth, water or wine, or a combination of these ingredients. To determine the proper amount of liquid, use about one third of the weight of the food. For example, if the fish fillet weighs about eight ounces (250 ml), the amount of liquid should be about two and half ounces (75 ml).
Do the final crimp and double-check the package to make sure it is securely sealed. Place the package on an oiled cookie sheet and put it into an oven preheated to the temperature indicated in the recipe. Bake for the specified time. The food is normally ready to serve when the package puffs from the steam and the paper turns a light brown color.
If parchment paper is not available, foil can usually be successfully substituted. However, if acidic ingredients such as wine, tomatoes or lemon juice are part of the recipe, the foil may produce aluminum salts that may slightly affect the flavor of the dish. This reaction may also create pinholes in the foil that make the liquid leak from the package.