Turkey Shawarma Pitas

Name: Turkey Shawarma Pitas
Ingredients: 1 small cucumber, finely chopped; 1 cup Greek yogurt; 2 garlic cloves, grated; 1 tablespoon chopped fresh or 1/2 tablespoons dried mint; 2 tablespoons dried dill; 1 teaspoon salt; 1/2 teaspoon pepper; 3 cups chopped turkey; 2 tablespoons butter; 1/2 teaspoon cumin; 1/2 teaspoon turmeric; 1/2 teaspoon paprika; 1/2 teaspoon coriander; 1/2 teaspoon sumac; 1/2 teaspoon onion powder; 1/2 teaspoon garlic powder; 1/2 teaspoon salt; Split, lightly toasted pita, feta, lettuce, and tomato (optional), for serving