Justice spooned the cooked grits over a mousse featuring leftover truffle bits, then topped the plate with chestnut and maitake mushrooms grown nearby with help from the restaurant’s compost. Nearly every component of the dish incorporated ingredients that might otherwise have been tossed — though customers would hardly know it from the price of the multicourse menu, which can run up to $160 for an “omnivore” version that includes wagyu short rib and scallops courses.Everything on HAGS’ menu aims to be zer ...