Soak poha in water for 15 minutes.
Drain water and set it aside.
Peel and grate radish, slice onions and keep them ready.
In a mixer grinder, grind poha into a coarse paste. Do not add water.
Now transfer poha to a bowl and add semolina, salt, radish and green chutney.
Mix it to make a thick dough.
Pinch it into small balls and set aside.
Heat a paniyaram pan, add oil in the moulds and fry the aval vadais in in until it is browned all around. Cook on medium flame so that the inside also gets cooked.
Alternately you can deep fry the vadas until golden.
Serve the vadas hot with ketchup.