1. Pulse the onion and garlic cloves in a food processor until they are finely minced. Remove the mixture and set it aside.
2. Add the chickpeas, parsley, salt, chili powder, cumin, and coriander to the food processor and pulse until they are roughly blended but not pureed.
3. Return the onion mixture to the food processor, along with the baking powder, peanut butter, lemon juice and about 1/4 cup of flour. 4. Continue to pulse the mixture and add more flour until it begins to form a ball and is not sticky. (You can add more flour than indicated if the mixture is still too wet.)
5. Transfer the falafel mixture to a bowl, cover it and refrigerate it for 30-60 minutes, depending on how much time you have to spare.
6. When you're ready to cook the falafel, heat a liberal amount of canola oil in a large pan/pot until it's hot enough to make a sizzling noise when tested with a piece of falafel.
7. Use a large spoon to form the mixture into small patties (you should end up with about 16, depending on the size you make them).
8. Roll each patty in flour and add them to the hot oil, one by one, frying them on each side until both sides are a nice golden brown and the inside is cooked.
9. Drain the falafel patties on paper towel and enjoy 3-4 on a pita topped with lettuce, tomato, cucumbers, and tzatziki.