Grilled Chicken Shawarma with Fennel Spina

Name: Grilled Chicken Shawarma with Fennel Spina
Ingredients: * 1 3/4 cup greek yogurt; * 1/2 cup plus 2 tablespoon olive oil; * 1 tablespoon fresh ground black pepper; * 1 tablespoon ground allspice; * 1 1/2 teaspoon ground coriander; * 1 1/2 teaspoon ground cumin; * 1 teaspoon cinnamon; * 1 teaspoon sea salt; * 8 clove garlic, minced; * 1 onion, grated; * wooden skewer, soaked in water for 30 minute; fennel spinach tzatziki sauce; * 1 tablespoon fresh lemon juice; * 1/2 cup cucumber, seed removed, finely chopped; * 1/2 cup frozen, chopped spinach, thawed, squeezed dry; * 2 tablespoon minced fresh dill; * 2 tablespoon minced fresh mint; * 2 tablespoon minced fresh parsley; * 1 small bulb fennel, outer layer removed, cored and finely chopped; * salt and fresh ground black pepper, to taste; for serving; * gluten free tortilla or pita bread, optional