Boil the sugar mixture until a 234 degrees or when a soft ball is formed when placed in cold water.
Remove the fudge from the heat and cool for 15 minutes, or until fuge mixture is lukewarm.
Add the butter, cookie butter, and vanilla. Stir to combine and pour into 8×8 pan that has been lined with foil. Let the fudge cool 5 more minutes, then cut and store in an airtight container.