Boil the water in a deep vessel. Add crushed fennel, 1 tsp sugar and ½ tsp salt to the boiling water. Lower the flame, add the rice flour in batches and keep stirring to avoid formation of lumps.
Switch off the flame once the rice flour soaks up all the water and forms a loose solid mass. Cover the vessel and let it stand for 15 minutes so that the rice flour gets cooked in the residual heat.
Remove the lid and allow it to cool down to a tolerable temperature. Sprinkle the ghee over the dough. Knead the mixture with your hands into a smooth dough. The kneading should be done when the dough is still hot, else the pitha will crack while frying.
Melt the jaggery with 2-3 tsp water in another wok. Once it starts foaming, add the grated coconut and cardamon powder to it. Cook for 3-4 minutes. Keep aside until it cools down.
Divide the dough into small balls. Flatten the balls. Stuff with the coconut mixture. Shape into small discs.
Now heat a wok. Add sufficient oil for frying.
When the oil is sufficiently hot, add the stuffed discs. Reduce flame to medium. Fry until the pitha is cooked and turns golden brown.
Remove from the wok and serve warm.