I love butterfinger candy bars, so I started getting creative and this recipe is the result. My daughter's friend liked it so much, she asked for the recipe so that she could make this candy as a birthday gift to her sister.
Lightly spray a 8x8 inch pan with vegetable spray or line with parchment paper. Combine chips, sweetened condensed milk, and marshmallows in a heavy saucepan over low heat, stirring constantly. When the mixture is completely melted and well blended, remove from heat. Stir in vanilla and chopped butterfinger bars.
Pour into prepared pan. Cool completely. I refridgerate to speed up the cooling process. If pan was lined with parchment, invert onto cutting board, invert again so that fudge is "right side up" and cut into squares. If pan was not lined with parchment paper, simply cut and remove from pan. Enjoy!