Sift together the dusting ingredients.  Grease a 13”x 9” (33cm x 23cm) pan with shortening or butter (Vegetable food release spray will not work) and coat the greased interior with dusting powder. Set the prepared pan aside and reserve the remaining dusting powder.

In a 1 qt (1 lt.) saucepan, add gelatin and water.  Let soak 5 minutes.  Add granulated sugar and stir over moderately low heat until the gelatin and the sugar dissolve. Pour heated mixture into the bowl of an electric mixer.  Add corn syrup, salt and vanilla.  Beat at high speed until stiff peaks forms, about 10 minutes.  Spread fluffy mixture in the prepared pan and smooth the top.  Allow the mixture to rest for two hours, until set.

Using a dinner knife with a wet blade, cut the marshmallow mixture into small squares.  Roll in dusting powder, and place on cake rack overnight, so that the outer surface dries slightly.