1. Soak the dhal (in plenty of water to cover) for 3 hours.
2. Wash and drain the dhal, ensuring that all of the grit has been removed.
3. Heat the oil. Fry the cloves and mustard seeds until they pop.
4. Add the washed and drained dhal and fry for a few minutes.
5. Mix in the remaining ingredients together with 2 cups of water (keep some coriander leaves aside for garnish).
6. Cook on low heat until the dhal is cooked. Remove from heat.
7. Prepare the mashed potato and mix with the dhal. Allow to cool.
8. For the pastry – Mix the salt and bicarbonate of soda with the flour. Add the oil and mix well with your fingers. Add a little water at a time and mix with your fingers. Knead until it forms a soft dough (you may need to add more than a cup of water). Place the dough in a bowl and cover with cling film. Set aside for 20 minutes.
9. Divide into 24 equal portions. Roll out each portion as for puri, about the size of a saucer.
10. Place a heaped tablespoon of the cooked mixture in the centre.
11. Wrap the pastry over the mixture. The pastry should be elastic in order to enable it to be stretched with your fingers to cover the dhal mixture to form a ball. Pinch to seal.
12. Deep fry in heated oil over medium heat until golden brown and crispy.
13. Drain on kitchen paper.