Drain the soaked chickpeas and kidney beans. Add them to a large pot with the lentils and enough water to cover. Cook until the beans become tender, about 60–75 minutes. Properly cooked legumes are essential for achieving the soup’s signature hearty texture.

Heat the vegetable oil in a large soup pot over medium heat. Add the chopped onion and cook until softened and lightly golden. Stir in the turmeric and black pepper, allowing the spices to bloom and release their aroma.

Add the cooked legumes and vegetable stock to the pot. Stir well and bring the mixture to a gentle simmer. This creates the flavorful base that ties all the ingredients together.

Stir in the parsley, cilantro, spinach, dill, and green onions. Simmer for about 20 minutes until the herbs soften and blend into the soup, creating its characteristic green color and fresh flavor.

Break the reshteh noodles into shorter pieces and add them to the pot. Stir frequently while they cook to prevent sticking. The noodles will absorb some of the liquid and help thicken the soup.

While the soup cooks, fry the sliced onions in oil until deeply golden and caramelized. In a separate pan, briefly fry the dried mint in a little oil for a few seconds until fragrant. Be careful not to burn it.

Season the soup with salt to taste. Ladle Ash Reshteh into bowls and garnish generously with caramelized onions, mint oil, and swirls of kashk. Serve warm and enjoy this comforting Persian classic.