1/8 cup Butter or Margarine (1/4 stick)
2 1/2 cup Sugar
2/3 cup Evaporated Milk (or Small 5 oz can)
10-12 oz Chocolate Chips
5-6 oz Marshmallow Creme
1 tsp Vanilla Extract
4 cups Salted popcorn
Prepare the popcorn and set aside.
Line a 9" x 13" pan with aluminum foil, scatter about 1-2 cups of popcorn in the pan and set aside.
Heat evaporated milk and sugar at Medium setting until warm. Bring to a rolling boil (Medium-High) while stirring constantly with a wooden spoon. Add the marshmallow creme - the rolling boil may stop. Bring back to a boil for  full minutes (by the clock-start once the boil resumes).
The mixture will start to turn brown during the boil. If you get brown flakes in the mixture then turn down the heat a little.
Remove from heat and add chips, vanilla, and butter to hot mixture. Mix thoroughly until the chocolate chips are fully melted. Add the remaining popcorn, fold over, and pour into prepared pan. Cool at room temperature. Remove from pan, remove foil, cut into squares.