Freeze-dried corn can be found with the other freeze-dried fruits and vegetables in many natural foods markets or online on amazon, walmart.com and target.com. But, if you can't find it, take 3/4 cup of defrosted frozen corn. Pat it dry with paper towels and spread it out on a parchment-lined baking sheet and roast at 350 degrees for 20 minutes. You may be able to go for longer, depending on your oven. The corn will have a little more "chew" than freeze-dried corn, but it will still be delicious! You can dehydrate the corn in a dehydrator if you have one, but I haven't tried that so I can't offer a time there.