Step 1

Place melted butter in a large bowl. Add granulated and brown sugars and stir until the mixture is smooth. Mix in egg and vanilla extract until combined.

Step 2

Mix in baking soda and salt, then slowly mix in flour and mix just until the batter is smooth and comes together. Be sure to scrape the sides of the bowl during stirring. Slowly mix in butterfinger pieces.

Step 3

Line a cookie sheet with a silicone baking mat or parchment paper. Scoop 2 tablespoon balls of dough onto the cookie sheet. Spacing doesn’t matter because you will be chilling the dough. Cover with plastic wrap and chill for at least 30 minutes.

Step 4

Preheat oven to 350°F. Line a second cookie sheet with parchment paper or a silicone baking mat.

Step 5

Remove the chilled cookie dough balls from the refrigerator and space them 2-inches apart on the cookie sheets. Bake for 11-15 minutes, or until the edges are a light golden and the tops are no longer glossy. Let cool on the cookie sheets at least 10 minutes before removing.