Corn syrup might seem like a key ingredient in making hard candy, but it's not even necessary. Making hard candy with straight sugar couldn't be easier.
Combine 1 cup sugar and 1 cup water in a pot. (To increase, use a 1:1 ratio of sugar and water.)
Stick the candy thermometer into the solution to monitor the temperature.
Bring the sugar syrup to a boil, up to about 300 degrees Fahrenheit, stirring occasionally.
Set out a cookie sheet and cover it with wax paper.
Carefully pour a drizzle of the sugar syrup over the cookie sheet. The syrup hardens almost immediately upon contact with the air and produces sugar candy.