Place the beans in a large pot or bowl. Cover with water and soak overnight. Drain and rinse.
Put the drained beans in a large pot and cover with water, one inch above the beans. Bring to a boil for 5 minutes. Remove any foam that rises to the surface.
Add the remaining ingredients.
Cover the pot and reduce the heat to low. Simmer until the water evaporates and the beans are soft. Set aside.
Place the shredded cabbage in a large bowl. Sprinkle with vinegar. Toss and let stand for 1 to 2 hours.
Add the onion, olives, parsley, and dill.
In a small bowl, mix together the oil, mustard, sugar, salt, and pepper. Pour over the salad and toss.
Taste and adjust seasonings.
Place all ingredients in a bowl and mix well.
Place 2-3 tablespoons of the beans on a tortilla.
Add 2 tablespoons of the cabbage salad.
Top with 1 tablespoon of the tzatziki. Drizzle with hot sauce, if desired.
Makes 12 6-inch tacos