In a large bowl, whisk cooled butter, brown sugar, and white sugar. Add in egg and vanilla and whisk in.
1/2 cup unsalted butter, 1/2 cup dark brown sugar, 1/3 cup white sugar, 1 tbsp vanilla, 1 egg
Add in the dry ingredients and mix until a soft cookie dough forms. Don't over-mix!
Add in the leftover halloween candy and mix in a few times.
Scoop 6 cookie dough balls (about 1.5 tbsp per cookie) and place on the prepared cookie sheet.
Bake for 10-15 minutes. Mine took 13 minutes. The cookies will be ready when the edges are a golden brown, but the inside will look very soft. Remove from oven, let the cookies cool on the hot pan for a few minutes before serving warm or cool completely and enjoy!
Notes
* You can use any leftover chocolate candy bars you have on hand! That's the beauty of this recipe.