To make the marinade, put the vinegar, dill, garlic, and mustard in a small jar. Add the miso and press it with a spoon to help disperse it. Seal tightly and shake until well combined. Season with pepper to taste.
Put the beans in a large bowl. Add the marinade and stir to coat the beans. Cover and refrigerate for at least 6 hours, stirring occasionally. Mix in the vegetables and option