Instructions

1. Line a 9- by 13-inch baking pan with wax paper.

2. Combine the confectioners' sugar and cornstarch and sift it evenly into the prepared pan. Pour the excess into a bowl.

3. In a bowl suitable for use with an electric mixer, place the unflavored gelatin and 1/2 cup water.
   Set it aside until the gelatin has softened, about five minutes.

4. Place the bowl in a larger pan of simmering water and stir until the gelatin has dissolved.

5. Add the granulated sugar and continue to stir until it has dissolved.

6. Removed the bowl from the warm water and drizzle in the corn syrup and vanilla while beating with an electric mixer for 10 to 15 minutes until creamy and thick.

7. With a wet spatula, spread the mixture in the prepared pan. Set aside for 20 minutes to cool and set.

8. Lift the set marshmallows out of the pan and place onto a cutting board. Lightly dust it with the confectioners' sugar and cornstarch mixture.

9. Cut the marshmallows into squares. Dredge the pieces in more of the sugar and cornstarch mixture -- so they won't stick to one another -- and store them in an airtight container in a cool dry place.