You can use either one of the following:
Fully Madras red round chillies
Half above + half Bedagi chillies
Half of first + half Kashmiri chillies.
Red chillies - 1 ¼ cup flat & loose
Dhaniya - 1 ¼ cups flat
Methi seeds - 2 heaped tsp
Mustard seeds - 1 heaped tsp
Jeera - 1heaped tsp
Peppercorns - 1 heaped tsp
Curry leaves - 5-6 sprigs
Roast red chillies in ¼ tsp oil till crisp.
Fry the other ingredients on a dry kadai.
Powder together in a mixie.
To prepare Mysore Rasam, please refer to
Mysore Rasam