Falafel Pitas with Cucumber-Yogurt Dressing

Ingredients:

• 1/4 cup minced red onion
• 1 tablespoon Dijon mustard
• 1 teaspoon ground cumin
• 1/2 teaspoon paprika
• 1/4 teaspoon newly ground black pepper
• 1/8 teaspoon salt
• 1 (15 1/2-ounce) can chickpeas (garbanzo beans), rinsed and drained pipes
• 1 (1-ounce) piece entire wheat bread, torn into pieces
• 1 big egg
• 1 big egg white
• 1 1/2 tablespoons olive oil
• 2 (6-inch) entire wheat pitas, split
• 1 cup arugula
• 1/2 cup Cucumber-Yogurt Dressing