Whisk yogurt, 1/2 cup cilantro, 1/4 cup onion, 1 garlic clove, lemon juice and 1/4 teaspoon cayenne in medium bowl to blend; season with salt and pepper. Refrigerate until ready to serve.
2
Blend garbanzo beans, 3 tablespoons flour, cumin, remaining 1/2 cup cilantro, 4 garlic cloves and 1/4 teaspoon cayenne in processor until almost smooth. Add egg and remaining 3/4 cup onion and blend, using on/off turns, until onion is finely chopped. Transfer mixture to bowl; sprinkle with salt and pepper. Shape mixture into four 1/2-inch-thick patties. Turn patties in remaining 1/2 cup flour to coat on both sides.
3
Pour enough oil into heavy large skillet to coat bottom; heat over medium-high heat. Add patties and cook until crisp and golden, about 8 minutes per side. Open pita breads; slide 1 patty, sliced tomato and lettuce into each. Spoon in some yogurt mixture.
