Preheat oven to 350 degrees and line cookie sheets with parchment or silpat liners.

In a medium bowl, combine the flour, cocoa, baking soda and salt. Set aside.

In a large bowl, cream together the butter and sugars until light and fluffy. Add eggs one at a time. Add vanilla and mix until well combined.

Stir in flour mixture until just combine. Then stir in crushed butterfinger and chocolate chips. Using a medium cookie scoop, drop by rounded spoonfuls onto prepared cookie sheets.

Bake for 9-11 minutes, should still be soft in center. Allow cookies to cool on baking sheet for 5 minutes before removing to a wire rack to cool completely. (High altitude changes: I reduced the granulated sugar to ¾ cup, add 1 tablespoon flour, and decreased the baking soda to 1 ½ teaspoons.)