Base marshmallow recipe adapted from [Alton Brown via Food Network|http://www.foodnetwork.com/recipes/alton-brown/homemade-marshmallows-recipe/index.html]
Yields: Approx. 8 dozen
Place the gelatin into the bowl of a stand mixer along with 1/2 cup of the water. Have the whisk attachment standing by.
In a small saucepan combine the remaining 1/2 cup water, sugar, corn syrup and salt. Place over medium high heat, cover and allow to cook for 3 to 4 minutes. Uncover, (clip a candy thermometer onto the side of the pan if you have one) and continue to cook until the mixture reaches 240 degrees F, approximately 7 to 8 more minutes. Once the mixture reaches this temperature, immediately remove from the heat.
Turn the mixer on low speed and, while running, slowly pour the sugar syrup down the side of the bowl into the gelatin mixture. Once you have added all of the syrup, increase the speed to high. Continue to whip until the mixture becomes very thick and is lukewarm, approximately 12 to 15 minutes.
Meanwhile, combine the powdered sugar and cornstarch in a small bowl. Lightly spray a 13 by 9-inch metal baking pan with nonstick cooking spray. Add the sugar and cornstarch mixture and move around to completely coat the bottom and sides of the pan. Return the remaining mixture to the bowl for later use.
Add the vanilla, orange zest, and orange juice during the last minute of whipping.
When ready, pour the mixture into the prepared pan, using a lightly oiled spatula for spreading evenly into the pan. Dust the top with enough of the remaining sugar and cornstarch mixture to lightly cover. Reserve the rest for later. Allow the marshmallows to sit uncovered in a cool place for 2-4 hours.
Turn the marshmallows out onto a dusted cutting board and cut into 1-inch squares using a pizza wheel dusted with the confectioners' sugar mixture. Once cut, lightly dust all sides of each marshmallow with the remaining mixture, using additional if necessary. Store in an airtight container for up to 3 weeks.