-
Place popcorn in a large bowl; set aside.
-
In a heavy saucepan, combine the brown sugar, water, corn syrup, butter and salt.
-
Bring to a boil over medium heat, stirring constantly.
-
Continue cooking without stirring, until a candy thermometer reads 270 degrees.
-
Remove from heat; stir in vanilla.
-
Pour over popcorn; stir until evenly coated.
-
When cool enough to handle, quickly shape into balls.
-
Wrap in plastic wrap.