1. Drain chickpeas well. In a food processor, pulse together the chickpeas, onion, garlic, parsley and cilantro, about 30 seconds.
2. Add the spices, salt, baking powder, and lemon juice; pulse just until blended, about 2–3 minutes. Scrape down the bowl of food processor when needed. Transfer to a bowl and stir in the seeds, taste and adjust seasoning with more salt or lemon.
3. Shape by heaping tablespoons into balls; flatten to 1/2 inch (1 cm) thickness. Arrange in a single layer on a baking sheet; cover and refrigerate for at least 1 hour.
4. Pour enough oil into a heavy skillet to coat the bottom of the pan; heat over medium-high heat and fry the falafel in batches, turning once about 4 minutes or until golden. With a slotted spatula or spoon, transfer to a paper towel-lined plate to drain.