1. Mix the butter, brown sugar and corn syrup in a microwaveable bowl.
2.Microwave on high for two minutes.
3.Stir mixture and microwave for two more minutes.
4.Add 2/3 cup sweetened condensed milk.
5.Microwave three more minutes.
6.Stir in 1/2 tsp vanilla.
7.Mix the popcorn and peanuts in a large container.
8.Combine the microwave mixture with the popcorn mixture.
Store in an airtight container.