You probably remember foil packet dinners from childhood camping trips, but the foil packets work just as well in the oven. The food steams quickly and evenly so meats and vegetables come out moist and flavorful. Steaming in packets also keeps more nutrients in the food than other cooking methods. Cooking in foil packets doesn't brown foods and it works best for small cuts of meat, such as fish, boneless chicken, beef and pork fillets, and sliced vegetables.
Preheat the oven to 375 degrees Fahrenheit. If you're using a convection oven, reduce the heat by 25 degrees.
Tear 10- to 12-inch squares of aluminum foil for single-serving packets, depending on how much food you want to put in each packet. Use larger squares for more food. Make one packet for each person instead of one large packet; food cooks quickly and evenly in smaller packets.
Mound chicken, fish and any vegetables on the foil, along with seasonings, such as salt, pepper and fresh herbs, or sauces on one side of the sheet of foil. Use condensed soups diluted with a little milk or water, salsa, teriyaki sauce, barbecue sauce or your own flavoring creations. If you use potatoes in the packets, boil or steam them first to soften them. Use instant rice rather than regular rice.
Add one or two ice cubes, or a bit of water to keep the vegetables and meat moist. If you're using a sauce, omit the ice cubes and water.
Fold the aluminum foil over and fold it down twice to form a tight seal. Seal the ends as well. Leave 1 inch of space around all edges so the heat can circulate freely.
Place the foil packets on a baking sheet and bake them until the vegetables are moist and the meat is cooked through. Cook chicken until a meat thermometer reads 165 F, according to the U.S. Department of Agriculture. Cook pork and beef or veal cuts to 145 F. Cook seafood to 145 F, or until the flesh is firm, white and opaque. Open the packets carefully wearing heat-safe gloves; the steam can burn your skin quickly.
Remove the baking sheet from the oven and allow the packets to cool for five minutes. Cut a few slits in the packet with a knife to allow the steam to escape.
Open the packets carefully. Transfer the food to plates or serve the food directly out of the foil. Clean-up is a cinch -- just crumple and throw the tin foil in the trash.