Preheat oven to 375 degrees.
Cream together butter, peanut butter and sugars.
Add egg and vanilla, mixing well.
In a separate bowl combine flour, baking soda, and salt with a whisk.
Add dry ingredients to wet ingredients.
Mix in 3 1/2 Butterfingers, chopped into dough.
Using medium scoop, (2 tablespoons worth) and scoop cookies onto baking sheet, with option to use fork for criss/cross. Leave room for cookies to spread.
Bake for 8-12 minutes or golden brown. Remove and let sit on cookie sheet for 2 minutes before removing to cookie rack. Cool completely.
Melt chocolate in microwave safe bowl in 30 second increments until chocolate is smooth. Place chocolate in pastry bag or ziplock bag with snipped tip and drizzle on top of cookies or dip half of the cookie in chocolate.
Add more Butterfinger chopped bits to top of cookies on wet chocolate and let set until chocolate hardens. Enjoy!