4 tablespoons butter or 4 tablespoons margarine, divided
2 medium onions, peeled and chopped
2 cloves garlic, peeled and chopped
3/4 teaspoon salt (or to taste)
1/2 teaspoon ground black pepper
1/2 teaspoon whole coriander seed
1 cup shelled walnuts, finely ground (AFTER measuring)
4 cups water
2 ounces vermicelli, broken into pieces
1 1/2 lbs tomatoes, chopped
1/4 cup chopped fresh parsley
1/4 cup chopped fresh cilantro