Sieve besan and rice flour together in a mixing bowl. Add salt, carom seeds, red chilli powder, and butter to it and mix well.
Slowly add some water and mix it to make a thick dough.
Keep aside for 10 minutes.
Place a thick bottomed pan on the flame and add oil to it.
Take a sev maker and stuff it with the dough. Slowly press the karapusa into the hot oil and fry till golden brown.
Take on to a kitchen towel to blot the extra oil.
Store in an airtight jar after cooling.