Pop 1 c popcorn to make 2 large roasting pans of popped corn, salted to taste.
In a saucepan, boil 2 c sugar, 1 stick Fleishmann's corn oil margarine, and optionally 1½ c green label Karo syrup food coloring until it reaches firm ball stage or 250 °F on a candy thermometer.
Cool slightly.
Drizzle over popcorn, stirring to distribute evenly.