Wash the lentils and cover with cold water in a bowl. Leave to soak overnight.
Drain the lentils and put them in a pressure cooker. Pour over enough water to cover them by about 3cm. Cook for 20-30 mins, until completely soft. Alternatively, cook them in a medium pan for about 1-1½ hrs until tender, adding extra water as needed to prevent them catching. Drain and leave to cool.
Tip the cooled lentils into a food processor and whizz to a paste. Transfer the paste to a heavy-bottomed frying pan and add the jaggery, fennel seeds, nutmeg and cardamom. Cook over a medium heat for 5-7 mins, stirring all the time, until the paste has thickened. Set aside to cool.
To make the dough, sieve the flour and salt into a mixing bowl. Rub the ghee into the flour with your fingertips, then add the saffron and its soaking water followed by enough cold water (about 100-125ml) to make a soft, but not sticky, dough. Knead in the bowl until smooth, then cover and leave to rest for 30 mins.
Knead the dough for 1 min, then divide into nine 40g portions. Shape each into a 4cm diameter ball with your hands. Shape the lentil paste into slightly smaller 3cm balls in the same way.
Make an indentation in the middle of one of the dough balls with your fingers, pressing it into a bowl-like shape. Put one of the lentil balls in the cavity and pull the dough around it, pinching the edges together so the lentil ball is completely enclosed. Flatten it to a 2cm-thick disc and roll it out on a lightly oiled surface to a circle 17cm in diameter. Aim for the thickness of a £1 coin.
Heat a griddle or heavy frying pan over a medium heat and carefully lift the disc onto the griddle. Drizzle 1 tsp of melted ghee around the edges and cook on one side for 2-3 mins, until it starts to colour. Flip over using a fish slice and spoon another 1-2 tsp melted ghee around the edges. Cook for a further 2-3 mins until golden. Repeat this process with the remaining dough balls. Serve straightaway with a glass of chilled milk or masala chai.