Gayle's Carmel Popcorn

This recipe came from my sister-in law, Gayle. It is soft and gooey, almost needs to be eaten with a spoon. But oh so good.

1 Cup Karo Syrup (dark)
1 stick butter
2 Cups brown sugar

Cook until forms soft ball when a small amount is dropped from a spoon into water. Remove from heat. Add 1 can sweetened condensed milk. Pour over popped popcorn and enjoy.