1 medium onion, diced
3 cloves garlic, minced
1 pound skinless, boneless chicken breast halves - cut into strips
1 teaspoon lemon pepper
1/2 teaspoon dried oregano
1/4 teaspoon allspice
1/4 cup plain yogurt
1/4 cup sour cream
1/2 cup cucumber, peeled and diced
4 pita bread rounds, cut in half