Preheat the oven to 400 degrees F (200 degrees C). Mix together ground chicken, onion, oil, paprika, cumin, oregano, pepper, coriander, 2 teaspoons salt, 2 teaspoons grated garlic, and 1/4 cup yogurt in a large bowl until well combined and smooth.
Divide meat mixture among 3 rectangular sheets of parchment paper (about 1 1/3 cups per sheet). Use a flexible spatula to spread meat all the way to the edges in a very thin layer, covering the sheet of parchment paper.
Starting with shorter end of the paper, fold meat-covered parchment several times in about 1 1/2-inch folds. Place folded, filled parchment on a large rimmed baking sheet.
Bake in the preheated oven until cooked through, 20 to 25 minutes, draining off some of the accumulated fat and juices halfway through.
Meanwhile, place grated cucumber in a fine mesh strainer set over a medium bowl. Toss with 1/4 teaspoon of the salt and let sit for 10 minutes, stirring occasionally. Press accumulated juices through strainer. Stir together drained cucumber, dill, 1 tablespoon of the lemon juice, remaining 3/4 cup yogurt, 1/4 teaspoon salt, and 1/4 teaspoon grated garlic in a bowl; set tzatziki sauce aside.
Unravel meat from paper, break into large pieces, and return to baking sheet. Toss with remaining 2 tablespoons lemon juice.
Serve meat on warm pita with tzatziki sauce, red onion, tomato, cucumber, and parsley. Serve with French fries, if desired. Recipe developed by Isabell Easter
