Into the bowl of a stand mixer fitted with the whisk attachment, or into a large heatproof bowl, pour half a cup of the cold water and sprinkle the gelatin over the top. Let stand for 10 minutes to soften.

In a heavy-bottomed saucepan, combine the granulated sugar and corn syrup with the remaining one-fourth cup cold water. Add the cinnamon and salt and stir over medium heat until the sugar is dissolved. Increase the heat and bring to a boil. Boil hard for one minute.

Pour the boiling syrup into the gelatin and beat at high speed in the stand mixer, or, using a handheld mixer, beat for 10 to 12 minutes, until the mixture is thick and white and has tripled in volume.

In a clean bowl, mix together the powdered egg white and the water to reconstitute. Beat with a handheld mixer until stiff peaks form. Add the egg white and the vanilla to the gelatin mixture and beat just until mixed thoroughly.

Dust a 10- by 15-inch jelly-roll pan with confectioners’ sugar. Pour the marshmallow mixture into the pan and spread evenly. Dust with one-fourth cup confectioners’ sugar and place, uncovered, in the refrigerator for three hours, or until firm.

Loosen the marshmallow mixture from the edges of the pan and turn out onto a cutting board. Slice into one-inch squares. Set aside.

Sift together all of the hot chocolate mix ingredients.

Using a wide funnel or spoon, pour one and a half cups hot chocolate mix into each of five eight-ounce jars. Top with cut marshmallows to fill the jar. (You will have extra marshmallows; reserve them for another use.)

Screw the lids in place and top with a circle of fabric and a raffia tie.

Include the following directions on a tag or label on the jar:

To Make the Hot Chocolate

Spoon one-fourth cup of mix into a mug. Heat one cup of milk until hot but not boiling. Pour the milk over the cocoa mix while stirring or whisking. Top with marshmallows.