Caramel Marshmallow Popcorn

1 pkg microwave popcorn, popped
1/2 c butter
1 c brown sugar
2 TBSP light corn syrup or honey
1/2 t vanilla
12 large marshmallows

1. Remove any unpopped kernels from popcorn.
2. Melt butter in a medium saucepan over low heat.
3. Add brown sugar, corn syrup, vanilla, and marshmallows
4. Turn heat to medium and stir until marshmallows are melted and mixture is smooth.
5. Pour over popcorn and stir in until popcorn is evenly coated.
6.  Store in airtight container.