In a large bowl add the drained chickpeas and mash with a fork or potato masher.
Add the onions, garlic, parsley, cumin, coriander, salt, and flour. Mash all the ingredients together to create a thick paste.
Form the mixture into small balls, a little smaller than a ping-pong ball.
Brush or spray all the falafels with oil.
Set up the BBQ for a fried-not-fried style cook. This method of cooking works particularly well in a kettle-style or round BBQ. Place the hot coals in the center only. You can use a vortex or kettle cone to help produce drier air circulation while minimizing the direct heat cooking. If you have a rectangular grill, place the coals to one side creating a hot zone and cool zone. If using gas, only light one side of the grill.
Place the falafel around the edge of the barbecue if using a round set-up or in the cool zone if using a rectangular grill. Cook for 30 minutes, rotating the falafel every 10 minutes. Serve hot.