Step 1

In a large bowl, stir together the chickpeas, 8 cups water, 1 tablespoon salt and 1 teaspoon of the baking soda. Let soak at room temperature for at least 12 hours, or up to 24 hours.

Step 2

Drain the chickpeas in a colander, rinse them and drain again. In a food processor, combine half of the chickpeas (about 2 cups), 2½ teaspoons salt, ½ teaspoon of the remaining baking soda, the baking powder, baharat and 1 teaspoon pepper. Process, scraping the bowl as needed, until the mixture is roughly chopped, about 1 minute. Add 1 cup water and continue to process until the mixture is mostly smooth, scraping the bowl as needed, about 2 minutes.

Step 3

Add the remaining chickpeas, parsley and cilantro. Pulse, occasionally scraping the bowl, until the mixture resembles very coarse sand; this will require about 60 pulses. Transfer the mixture to a medium bowl. Cover and refrigerate for at least 1 hour or up to 3 hours.

Step 4

When you are ready to fry the falafel, set a wire rack in a rimmed baking sheet. Into a large (7- to 8-quart) Dutch oven over medium-high, add oil to a depth of about 1½ inches and heat to 325°F. When the oil is nearly to temperature, remove the chickpea mixture from the refrigerator. Add the lemon juice and remaining ½ teaspoon baking soda to the chickpea mixture; stir until well combined.

Step 5

When the oil reaches 325°F, use a 1¾-inch (2-tablespoon) spring-loaded scoop to scoop up a portion of the chickpea mixture, lightly compacting the mixture into it against the side of the bowl. Holding the scoop just above the surface of the oil to prevent splashing, carefully release the portion into the oil. Working quickly, scoop an additional 8 or so portions into the pot. Fry, occasionally rotating the falafel, until deep golden brown, about 5 minutes; adjust the heat as needed to maintain an oil temperature of 300°F to 325°F.

Step 6

Using a slotted spoon, transfer the falafel to the prepared rack. Cook the remaining chickpea mixture in the same way, stirring the mixture as needed to reincorporate any liquid that separates out and allowing the oil to come back up to temperature before adding subsequent batches.

Step 7

Serve the falafel with the tahini-yogurt sauce, pita and tomatoes.