Instructions

  1. Preheat oven to 350°F.
  2. Grease an 8" square baking pan.
  3. Combine the flour and both sugars in a large bowl; cut in the butter until the mixture is crumbly.
  4. Transfer 1/2 cup of the crumb mixture to a small bowl; stir in the Butterfinger pieces.
  5. Stir the baking soda and salt into the remaining flour mixture; set aside.
  6. Combine the milk, sour cream, egg, and vanilla in a small bowl; blend well.
  7. Add to the flour mixture; stir just until combined.
  8. Pour the batter into the prepared pan; sprinkle evenly with the Butterfinger crumbs.
  9. Bake for 40-45 minutes, or until a toothpick tests out clean.
  10. Cool on a wire rack at least 20 minutes before cutting.
  11. Serve warm or cool.