To a food processor, add chickpeas, yellow onion, flour, parsley, whole garlic, baking powder, cumin, coriander and salt and pulse to a grainy paste, scraping down bowl as necessary. With lightly moistened hands, shape paste into 12 golf ball-size rounds, arranging on a plate.Coat a very large nonstick skillet with cooking spray and heat on medium-low. Working in batches if necessary to avoid crowding the skillet, add balls and use a spatula to flatten to about ½ inch thick. Cook until browned on bottom, 4 to 5 minutes. Flip and brown other side, 4 to 5 minutes.Meanwhile, in a small bowl, whisk together tahini, ¼ cup water, lemon juice, remaining minced garlic and paprika.Cut about 1 inch off top of each pita, forming a pocket. Add 2 falafel to each pita and divide lettuce, tomato, cucumber, pickle, red onion and tahini sauce among pitas. Drizzle each with harissa (if using).Find more plant-based recipes here!We independently source all of the products that we feature on cleaneatingmag.com. If you buy from the links on our site, we may receive an affiliate commission, which in turn supports our work.