Soak the garbanzos overnight in water (at least 12 hours, I usually wait 24). When ready to prepare, drain them and put them through a food grinder with the onion, potato and garlic. Add the seasoning and flour, mix and let sit for about 2-3 hours.
When you are ready to deep fry, add the baking soda and mix again. Heat about 2-3 inches of Canola oil in a deep, heavy frying pan to just below smoke point. Form mixture into patties about the size of a golf ball, flatten slightly, and place in the oil for about 2 minutes, turning a couple of times. Remove with slotted spoon and drain on paper.
Serve on warm pita with whatever you like on your falafel.
*A note to those who use canned grabanzos: using canned (cooked) garbanzos is not doable since the patties basically melt in the deep frying process. I don't know what secret you use to keep the patties together, but I tried it like that once - following the recipe to a T -they disentegrated in a matter of seconds. Uncooked beans is the only way to go in my opinion.