1.Place chickpeas in a large bowl and cover with cold water. Stand overnight, drain.
2.Combine chickpeas, onion, garlic, parsley and spices in a large bowl. In two batches, blend or process chickpea mixture until almost smooth. Return mixture to bowl.
3.Add soda, flour and salt to chickpea mixture. Stir to combine, season. Stand 30 minutes.
4.Roll level tablespoons of mixture into balls; stand 10 minutes.
5.In batches, deep-fry balls in hot oil until golden brown. Drain on absorbent paper.