Heat oil in a pan. Crackle mustard, hing and fennel seeds in it. Add turmeric powder and both the soaked dal with 1/2 cup water.
Add salt and coriander powder also.
Cover the pan with a lid until it is cooked and all water evaporates.
Then add garam masala and roasted besan.
When it cools down, grind it coarse.. The stuffing is ready.

For the dough,
1 cup wheat flour with a pinch of salt is required. Knead a soft dough using this.