4 T vegetable oil
2 cups unpopped popcorn
1/4 cup butter
1 cup packed light brown sugar
1/2 cup light corn syrup
2/3 cup sweetened condensed milk
1/2 t vanilla
Add 3 kernels of popcorn to 2 T oil in a large saucepan and heat over high heat. When kernels pop, add 1 cup of popping corn. Keep pan moving gently until popping slows and stops. Remove from heat. Pour into very large bowl or pan (I use a roasting pan) and repeat.
In a medium saucepan, combine butter, sugar and corn syrup. Stir well and bring to a boil over medium heat. Stir in condensed milk; simmer, stirring constantly for about 3 minutes and stir in vanilla.
Pour over popcorn and stir with wooden spoon to coat. Spread in one layer on waxed/cooking paper or butter hands and shape into 3.5-inch balls. Allow to set before storing in plastic bags.