Cover a baking pan completely in aluminum foil, and spray the foil down with cooking spray.

Whisk together 1/4 cup water, the corn syrup and the sugar in a sauce pan.  Place the sauce pan over medium heat and continue to whisk until the sugar is dissolved.  Let the sauce pan alone over the heat until it comes to a hard boil.  Let your sugar mixture remain at a hard boil for 1 minute until it looks like the picture below.  Once it reaches that consistency, immediately take it off the heat and beat it gradually (on either low or medium) into the gelatin.  Be careful to pour the sugar along the side of the bowl and not let the hot sugar touch the beaters upon entry.

Continue beating on low for 12 minutes.  Seriously, 12 minutes.  Set your alarm.  You will be there a while.

You may believe the consistency you’ve reached is thick enough, but it probably isn’t.  You want the mixture to form stiff, stiff peaks.  12 minutes.

Pour the marshmallow mixture into your pre-lined pan (this pan was 9″x6″), being careful to scrape down the sides with a rubber spatula.  Let it sit there are room temperature for at least 3 hours or overnight.

Once the marshmallows have set, it is best to cut them with scissors.  Be sure to oil the scissors before cutting.  I cut lengthwise, then cross-wise 1″x1″x1″ cubes.

Mix together the powdered sugar and the cornstarch.  Dredge each piece in the mixture until covered.  If you don’t do this, your marshmallows will stick together.  You may omit the corn starch and use just powdered sugar if you’d like.