Slice the onions and mince the garlic. Rinse the chicken, remove the skin, and cut the chicken breast into bite-sized cubes. Bone-in chicken thighs will add depth and richness to the soup. Peel the ginger and cut it into large pieces. Rinse the lentils and barley, discarding any impurities and floating husks.
Lower the heat and add spices, two tablespoons of oil, and half a cup of water, stirring to combine. Add the chicken and cook for three minutes until it turns white.
Pour in three litres of water, cover, and bring to a boil. Then add the lentils and barley, stirring gently. Reduce the heat to low and simmer with the lid closed for 1.5 hours, stirring every seven to ten minutes to prevent sticking. Once cooked, serve the hearty and creamy Haleem with lemon, buttered bread, and herbs as garnish.