The epic Smash Burger starts with perfectly prepared meat, but the secret may literally be in the sauce. Restaurant chains and convenience stores that specialize in their burgers have their own versions, but most traditional sauces include at least sweet relish, ketchup, mayonnaise and vinegar.
The perfect sauce for a Smash Burger should be balanced. They can’t all be high in fat, added sugars, or tart vinegar. Start with a 2:1 ratio, mayonnaise to ketchup, then customize as you see fit. Add vinegar if you like a little tang (red wine or cider is a classic). Prefer more sweetness? Add sweet pickle flavour.
For a delicious version similar to Shake Shack sauce, consider skipping the sweet pickle relish and substituting it with dill pickle brine. Although their actual recipe is a secret, the dill pickle brine is definitely there, followed by the burn of chili and the flavor of Dijon mustard. But don’t think too much about it. Burger connoisseurs may skip the fancy sauce altogether and opt for classic ketchup and mustard.