Part 3/8:
Taste and adjust the seasoning as needed. Set aside to rest; this will be used both as a condiment and to add extra moisture to the sandwich.
Preparing the Onions
Caramelized onions are the heart of a good patty melt. They require patience and careful attention:
Chopping: Slice the onions root-to-stem, in rings or strips.
Initial Cooking: Heat a large pan (preferably 14 inches) with a couple of tablespoons of olive oil, a pinch of salt, and a splash of water. Turn the heat to high until the pan is hot. This rapid initial step helps to loosen the water content, softening the onions quickly.