There's just today and one more Thursday in the month of September to get your taste (your fix?) of Balsamic-Fig custard from Shake Shack. The custard is equal parts balsamic and fig in flavor, none too strong, both pleasant and mild. Much less exciting that I had hoped for, but satisfying nonetheless. My only request? For chunks of fresh figs to be mixed in à la their Coffee and Doughnuts flavor.