If you’re going to be baking them, preheat the oven to 200°C / 400°F
Chop up the ginger, green onions and mushrooms finely, and sauté in about half of the olive oil until the mushrooms are wilted and brownish.
In the meantime, chop up the nuts. Add to the sauté pan to toast a bit.
If using the fermented black beans, chop finely until they’re almost a paste.
Reserve a couple of spoonfuls of the beans. Mash up the rest of the beans with a masher or in the food processor. Put the fermented black beans in and process until it’s fairly smooth. Add the spice and rice flour and process again. Add the sautéed vegetables, the reserved beans and the nuts, and pulse-process until mixed (you want some of the texture to remain).
Divide the mixture into 8 to 12 portions. With moistened hands, make into flat little patties.
If baking in the oven, oil a baking sheet and then brush the tops with a bit more oil. Bake for about 10 minutes, flip then bake 5 minutes more.
If cooking in a frying pan, heat up the pan with the rest of the oil. Fry the burgers until crispy, carefully flip over and fry the other side.
In the meantime, mix the sauce. Brush the sauce onto the hot burgers, or serve separately for dipping.
Good hot or at room temperature.