First mix the miso with olive oil and combine well. Then add the brown rice vinegar and water to complete the dressing.
Mix the dill into the three tablespoons of miso dressing (reserve the rest of the miso dressing for salad another time). Cut the tomatoes into small cubes, mix into the beans and spring onions and refrigerate for at least 1 hour. Serve the beans on a plate with slices of avocado, a sprinkling of nigella seeds and a drizzle of dressing.