Best Portobello Burgers

No matter how many variations on a hamburger that a typical burger joint menu offers, the prevailing way of preparing portobello mushroom burgers—and the vegetarian portobello-as-meat default—at restaurants seems to be to drench them in cheap, cloyingly sweet balsamic vinegar marinade. The first thing I realized when I began developing my portobello burger was that the mushroom needed a savory marinade to double down on the mushroom’s inherent umami characteristics. Enter miso paste! For ye