In the bowl of your food processor, add chickpeas, onions, parsley, and garlic (I have a very tiny processor and just did this in 3 batches). Process until pieces are small but haven’t turned into a paste. You want it a little chunky. Pour into a large bowl and add egg, cumin, coriander, salt, pepper, lemon juice, and baking powder. Stir together to make sure everything is evenly distributed. Add bread crumbs and combine.