Open-Faced Falafel burgers

Ingredients

Sauce:
1 cup hot water
1/4 cup tahini (sesame-seed paste)
3 tablespoons fresh lemon juice
1/8 teaspoon salt
2 garlic cloves, minced

Patties:
1 cup chopped red onion $
1/2 cup chopped fresh parsley
2 tablespoons fresh lemon juice
1 teaspoon ground cumin
1 teaspoon ground coriander
1/2 teaspoon salt
2 (15 1/2-ounce) cans chickpeas (garbanzo beans), drained
4 garlic cloves, minced
1/2 cup dry breadcrumbs, divided
4 teaspoons olive oil, divided

Remaining ingredients:
6 mini pitas (about 5 inches wide)
3 cups chopped romaine lettuce
2 cups chopped tomato
2 cups sliced peeled cucumber
1/2 cup finely chopped red onion

Preparation

To prepare sauce, combine the first 5 ingredients in a blender, and process until smooth.
To prepare patties, combine 1 cup onion and next 7 ingredients (through 4 garlic cloves) in a food processor, and process until smooth, scraping sides of bowl occasionally. Place bean mixture in a large bowl; stir in 1/4 cup breadcrumbs. Divide bean mixture into 6 equal portions, shaping each into a 1/2-inch-thick patty. Place remaining 1/4 cup breadcrumbs in a shallow dish. Dredge patties in breadcrumbs.
Heat 2 teaspoons oil in a large nonstick skillet over medium-high heat. Add 3 patties to pan; cook 3 minutes on each side or until browned. Repeat procedure with remaining 2 teaspoons oil and patties.
Warm mini pitas according to package directions. Place 1 pita on each of 6 plates. Top each serving with 1/2 cup lettuce, 1/3 cup tomato, 1/3 cup cucumber, and 4 teaspoons onion. Drizzle each serving with about 3 tablespoons sauce; top each serving with 1 patty.