5mint leavesthinly sliced (substitute dill, if you prefer)
Cut the chicken breasts into ½-inch thick strips. Place in a resealable plastic bag.
In a medium bowl, whisk together the lemon juice, olive oil, cumin, coriander, smoked paprika, salt, allspice and cinnamon. Pour into the bag with the chicken. Seal the bag and massage the chicken to coat with the marinade.
Marinate for at least 1 hour, but preferably overnight.
Preheat the grill to medium-high heat. Lightly coat the grate with oil. Cook until the chicken is just cooked through, 2 to 3 minutes per side. Let cool slightly, then cut into bite-sized pieces.
Serve with the tzatziki, pita bread, hummus and pickles.
The Avocado Tzatziki:
Place the grated cucumber in a piece of cheesecloth or a thin kitchen towel. Wrap and squeeze out the liquid. Set aside.
In the bowl of a food processor, combine the avocado, yogurt, lemon juice, garlic and salt. Puree until smooth, scraping down the sides as needed.
Transfer the sauce to a bowl, and stir in the cucumber and mint.