Ingredients

• 8 ounces plain yogurt
• ⅓ cup chopped seeded cucumber
• 2 tablespoons finely chopped onions
• 1 garlic clove, minced
• 1 teaspoon sugar
• 1 lb lean ground beef (I use ground turkey)
• 1½ teaspoons dried oregano
• 1 teaspoon garlic powder
• 1 teaspoon onion powder
• 1 teaspoon salt (optional)
• ¾ teaspoon pepper
• 4 pita breads
• 3 cups shredded lettuce
• 1 large tomato, chopped
• 1 small onion, chopped

Preparation

1. In a bowl, combine first 5 ingredients.
2. Cover and refrigerate.
3. In separate bowl, combine ground beef and seasonings.
4. Mix well.
5. Shape into 4 patties.
6. Grill, covered, (you can also use a toaster oven or broil these) over medium to high heat for 10 to 12 minutes or until meat is no longer pink, turning once.
7. Cut patties into thin slices.
8. Stuff into pitas.
9. Add lettuce, tomato, and onion.
10. Serve with yogurt sauce.

Source: http://www.food.com/recipe/ground-beef-gyros-30081