Karela Posto is a traditional Bengali dish made with bitter gourd and poppy seeds. The bitter gourd is first marinated in salt to reduce its bitterness, then cooked with a paste made from poppy seeds, mustard oil, and spices. The dish has a unique combination of flavors, with the bitterness of the gourd balanced by the nuttiness of the poppy seeds. Karela Posto is a popular side dish in Bengali cuisine and is often served with rice or roti.