2 garlic cloves, chopped
1 small onion, quartered
1 tablespoon cumin
Scant teaspoon cayenne, or to taste
1 cup chopped fresh parsley or cilantro
1½ teaspoons salt, plus more to taste
½ teaspoon black pepper, plus more to taste
½ teaspoon baking soda
1 tablespoon fresh lemon juice
4 tablespoons olive oil
½ cup tahini
1. Put the chickpeas in a large bowl and cover with water by 3 or 4 inches—the beans will triple in volume as they soak. Soak for 12 to 24 hours, checking once or twice to see if you need to add more water to keep the beans submerged. (If the soaking time is inconvenient for you, just leave them in the water until they’re ready; you should be able to break them apart between your fingers.)
2. Heat the oven to 375°F. Drain the chickpeas and transfer them to a food processor with the garlic, onion, cumin, cayenne, herb, 1 teaspoon of salt, pepper, baking soda, and lemon juice. Pulse until everything is minced but not pureed, stopping the machine and scraping down the sides if necessary; add water tablespoon by tablespoon if necessary to allow the machine to do its work, but keep the mixture as dry as possible. Taste and adjust the seasoning, adding more salt, pepper, or cayenne as needed.
3. Grease a large rimmed baking sheet with 2 tablespoons of the oil. Roll the bean mixture into 20 balls, about 1½ inches each, then flatten them into thick patties. Put the falafel on the prepared pan and brush the tops with the remaining 2 tablespoons oil. Bake until golden all over, 10 to 15 minutes on each side.
4. Meanwhile, whisk the tahini and remaining salt with ½ cup water in a small bowl until smooth. Taste and adjust the seasoning and serve the falafel drizzled with the sauce.