1. Drain and rinse the chickpeas and fava beans, and put them in the bowl of a food processor. Add the onion, parsley, cilantro, garlic, cumin, salt coriander, crushed red pepper, baking soda, and lemon juice. Process, scraping down the sides of the bowl with a rubber spatula as necessary, until the mixture is uniform and can hold a shape when gently pressed together with your fingers. Transfer the mixture to a bowl, cover, and set aside for 30 minutes.

2. Using a 2-tablespoon scoop, portion out the fava-chickpea mixture. Then gently form the scoops into patties. Set them aside on a plate.

3. Fill a 12- to 14-inch saute pan with vegetable oil to a depth of 1 1/2 inches, and heat it to 350°F. Using a metal spatula and working in batches, making sure not to crowd the pan, gently lower the falafel patties into the hot oil and fry until they are crisp and brown on one side, 1 1/2 to 2 minutes. Flip the patties over and cook until crisp and brown on the other side, 1 1/2 to 2 minutes longer. Transfer the patties to a paper-towel-lined plate and repeat with the remaining mixture.

4. To assemble:  Cut each pita bread to form a pocket, and fill it with some Cucumber, Onion, and Tomato Salad, falafel patties, Tahini Sauce, and hot sauce if desired. (Alternatively, you can wrap the ingredients in the pita, or place the components on a platter and allow guests to serve themselves.)