Combine gelatin with 1/2 cup of cold water and set aside.

Cook the granulated sugar, corn syrup, salt, and 1/2 cup water in a saucepan over medium heat until the sugar dissolves.

Raise the heat to high and cook until the syrup reaches 240 degrees – watch carefully to monitor the temperature and avoid burning.

Once the syrup mixture reaches temperature, remove from heat and slowly pour the sugar syrup over the dissolved gelatin in the bowl of a stand mixer on low; add in the vanilla extract.

Turn the mixer up to high speed and whip until thick, for about 15 minutes.

Once thickened, pour the mixture out into an 8x12 baking dish that has been generously dusted with confectioners' sugar.

Add more confectioners' sugar over the smoothed out top, and set out to rest uncovered overnight.

After resting the marshmallows over night, turn them out onto a board and cut them in squares or press with cookie cutters into shapes.

Dust with more confectioners' sugar before packaging and serving (try it with Green Mountain Coffee® Toasted Marshmallow Mocha Coffee!).