Blitz bread in a food processor until you have chunky crumbs. Add chickpeas, onion, parsley, cumin and a little salt. Blitz again until you have a paste that is still a little chunky.
Using a tablespoon and your hands form into rounds or little logs that are about the size of a walnut in its shell.
Heat enough oil to just cover the falafels in a medium saucepan until very hot. When a piece of bread browns in 10 seconds or so, add about 1/3 the falafels and fry for a few minutes or until deep brown. Remove and drain on a wire rack. Keep warm while you repeat with the remaining batches, making sure the oil is hot enough between each.