Firstly, add wheat flour to mashed potato along with red chili powder, coriander powder, asafoetida/hing, turmeric/haldi powder, carom seeds, fennel seeds, sesame seeds, coriander leaves, salt and oil.
Mix them well and add water to form a dough. Keep it aside for few minutes.
Make small round balls of this dough and roll them in the form of a puri
Apply oil on the rolling pin and rolling board and carefully roll them in to Puri.