In a medium size bowl, combine together 1 cup besan, 1/2 tsp salt and add water gradually to make a smooth batter. I used around 1/3 cup + 1 tbsp water. The batter should be of pouring consistency. It should be medium thick, not too thin or too thick.
In another medium size bowl, combine together 1 cup besan, 1/4 cup water, 2 tsp oil and 1/2 tsp salt. Make a smooth dough. The dough may be a bit sticky initially but after kneading for a while, it becomes soft.
To make sev (noodle shapes): Heat oil in a deep and wide pan. Once the oil has the reached the desired temp (refer notes), press the dough through Idiayappam / seva mould into the hot oil in circular motion. Fry each side for 30 - 45 seconds (depending on the temp of oil) till it reaches a golden color. Keep in mind that the sev gets cooked very fast, so keep a close watch while frying the sev. Transfer it to paper towels and let it cool.
To make boondhi: In the same pan, pour the batter through a perforated spoon / ladle into hot oil. Fry for 45 seconds or so till the boondi becomes golden color. Make sure not to overcrowd the pan while frying. Transfer to paper towels and let it cool.
In the same pan, fry the cashew nuts, peanuts, roasted gram dal and curry leaves separately. Transfer to paper towel.
Take a large size bowl and add the sev. Break it into small pieces using your fingers. Add boondhi and other fired items. Add kashmiri chilli powder, asafoetida and salt (if required). Mix well. You can also add small pieces of banana chips at this stage. Once it's cooled completely, store in an airtight container.