Shake Shack released a cookbook online and in stores called, Shake Shack Recipes & Stories. It's filled with crinkle fries, custard shakes and the infamous Shack sauce (Sos).
So you don't go searching all over the internet for the recipe, I saved you the trouble!
½ cup Hellman’s mayonnaise
1 tbsp Dijon mustard
3/4 tsp Heinz ketchup
¼ tsp kosher dill pickling brine
Pinch of cayenne pepper
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