Whisk the egg whites in a mixer on high speed until soft peaks form.

In the meantime, combine the sugar, corn syrup, water, and salt in a saucepan.

Cook over medium heat until it reaches a boil. Continue cooking, stirring constantly, until a candy thermometer indicates that the mixture reached 270 degrees Fahrenheit, soft crack stage. (This should take a minimum of 20 minutes).

While the mixer is running, slowly pour the hot syrup into the egg whites. Continue to beat until the mixture is stiff and glossy, about five minutes.

Add the vanilla extract, margarine, and melted chocolate.

Add cocoa and beat until combined.

Pour the mixture into a Gefen Parchment-lined baking pan and refrigerate overnight. The size of the baking pan depends on the desired outcome. If you want high pieces of nougat then use an eight- by eight-inch pan; for nougats that will be rolled for candy, use a nine- by 13-inch pan.

Use a fine-tipped paint brush to coat the chocolate mold with melted chocolate. Place the mold in freezer for a couple of minutes.

Remove from the freezer and check to make sure the entire surface has been coated; if necessary, apply another coat of chocolate.

Once the outside coating of chocolate is set, drop a piece of nougat into the mold.

Cover with a thin layer of melted chocolate. Let the chocolate set for one hour before removing it from the mold.