Cooking the sugar into a two-thread syrup before adding to the halwa ensures it sets without graininess. Continuous stirring is essential to prevent the lentils from sticking and to achieve that characteristic sheen as ghee separates. Buter Daaler Halwa is made from split Bengal gram (chana dal). It requires patience and slow cooking, making it a delicacy usually reserved for special occasions like weddings, pujas, Eid or Shab-e-Barat.