holiday treats--popcorn balls

2 cups brown sugar
1 cup white corn syrup
bring to a boil, making sure the brown sugar is well melted before it boils.
add:
1 can sweetened condensed milk
1/4 lb. butter
bring all ingredients to a boil, then add 3/4 tsp. vanilla.
pour the sauce over the popcorn in a large brown paper bag and shake.