Put the chickpeas, scallions, parsley, cumin, garlic powder, salt, pepper, and 2 tablespoons flour into a food processor fitted with the steel blade. Process until the mixture becomes a coarse paste. Divide the mixture into 6 equal portions and shape into patties. Put the rest of the flour on a plate. Place the patties in the flour and coat well on both sides.
Heat the olive oil in a large skillet over medium-high heat. Add the patties and cook for 2-3 minutes per side or until crispy.
To serve, place the falafel burgers on lettuce leaves. Top each burger with a dollop of Creamy Tahini Sauce. Add a dab of chili garlic sauce if desired. Serve the rest of the tahini sauce on the side.