Line bottom and sides of 8-inch (2 L) square baking dish with foil; set aside.
Stir together sugar, evaporated milk and salt in large glass bowl until thick and grainy. Heat in microwave on high for 2 minutes then whisk for 10 seconds. Return to microwave; heat for another 1 minute.
Whisk in cookie butter; heat for 30 seconds. Using wooden spoon, stir vigorously for a few seconds then heat for another 30 seconds. Remove from microwave and stir very well; immediately pour into prepared pan, smoothing top with wooden spoon. Let cool on counter for a few minutes then refrigerate to cool completely.
Lift fudge from pan; remove foil and cut into 64 squares.