1. Place chickpeas in a large bowl and add enough water to cover by 3 inches. Place bowl in refrigerator and let soak until the chickpeas swell to double their size, at least 12 hours and up to 24. Drain and rinse thoroughly.

2. Transfer rinsed chickpeas to the bowl of a food processor and pulse until well ground (about the consistency of cornmeal). Add onion, garlic, parsley, cilantro, mint, cumin, coriander, baking powder, salt, and pepper; process until mixture is pureed, scraping down sides as necessary. Falafel mixture can be made 3 to 4 days in advance and kept refrigerated in an airtight container until ready to use.

3. Fill a countertop electric fryer or a deep pot 3 inches high with oil. Heat until it reaches 350 degrees on a deep-fry thermometer. Using your hands, form falafel mixture into a 1 3/4-inch balls, pressing tightly so that falafel does not fall apart while frying.

4. Using a slotted spoon and working in batches, carefully add falafel to hot oil, gently nudging so they do not stick to the bottom. Fry, turning as needed, until crusty and dark brown on all sides, about 5 minutes. Transfer falafel to a paper towel-lined plate to drain. Serve immediately with tahini and pickled vegetables.