Special equipment: a deep-fry thermometer
For the sauce: In the bowl of a food processor, add the tahini, lemon juice, olive oil, garlic, chipotle and adobo sauce and salt and pepper to taste and process until smooth. If it is too thick, add some water a couple tablespoons at a time until it is the consistency of heavy cream. Scrape into a bowl, cover and refrigerate until ready to serve.
For the falafel: Using the same processor bowl, add the chickpeas and process until coarsely ground. Add the flour, parsley, cilantro, baking powder, cumin, cayenne, scallion, 1 teaspoon salt and 1/2 teaspoon pepper and process until well mixed but not totally smooth. Check the consistency to make sure it will hold together. If it is too dry, add some water a little at a time. Taste and adjust the seasoning.
Add about 2 inches of vegetable oil to a deep skillet and heat until a deep-fry thermometer registers 325 degrees F.
Using a small scoop or a tablespoon, scoop out small balls of the falafel mixture and gently drop them into the hot oil. Cook in batches, turning them over from time to time, until golden brown and cooked through, for between 30 and 60 seconds. Drain on paper towels while you cook the rest.
To serve: Cut the top off each pita and form a pocket. Drizzle some sauce into each pita and add 4 or 5 falafel pieces. Top with the greens, carrots, scallions and plenty more sauce. Alternatively, build a salad with the vegetables, then top with falafel and sauce.