While Mary Nguyen is primarily known for her Asian and French fusions at P17 and Olive & Finch, one of her menu standouts is not a dish, but a sauce. At Olive & Finch, the chimichurri that comes on the D.F. (a beautiful mess of eggs, pulled pork, green chile and cheese) and the Nico sandwich, her version of a Spanish cheesesteak, features the perfect blend of graininess and heat, and is so good we could put it on just about anything. Made in-house from parsley, red-pepper flakes, garlic, lemon juice, red-wine vinegar and neutral-flavored oil, it sounds like a simple recipe — but the result is anything but. Quite possibly what Dr. Seuss was preaching about in Green Eggs and Ham, this magical sauce spruces up everything it comes into contact with, from proteins to potatoes.