caramel for caramel popcorn

Not sure how much popcorn this covers....

Dad's Caramel Popcorn

1 cup sweetened condensed milk
1 cup karo syrup
1 cup brown sugar
1 cube butter

Put plain popped popcorn in large brown paper bag.
Combine ingredients in medium saucepan over medium-high heat,
stirring constantly. (be careful not to splatter -you'll get burned.)
When sugar is dissolved, butter melted and it thickens a bit, carefully
pour over popcorn and stir with a wooden spoon.