Rather than antonyms for the phrase "made hash of," it might be more helpful to consider alternative phrases that have a similar meaning but use different words. Some possible alternatives include "botched up," "messed up," "bungled," "butchered," "screwed up," or "made a mess of." These phrases all describe a situation in which something was done poorly or incorrectly, resulting in a negative outcome. Antonyms for "made hash of" might be phrases such as "executed expertly," "handled with care," "performed flawlessly," or "handled with precision," which describe situations in which something was done well and achieved a positive outcome.