1. Stir together yogurt and lemon zest in small bowl. Set aside.

2. Wrap grated zucchini in clean kitchen towel, and wring out excess moisture.

3. Whisk egg in large bowl. Stir in zucchini, green chiles, green onion, and garlic. Sprinkle mixture with flour and baking powder, and stir to combine. Season with salt and pepper, if desired.

4. Heat 1 Tbs. oil in large skillet over medium heat. Drop 6 heaping tablespoonfuls zucchini mixture into skillet, and gently flatten. Cook 2 to 3 minutes per side, or until golden brown. Transfer to paper-towel-lined plate, and repeat with remaining zucchini mixture.

5. Spread 2 Tbs. hummus inside each pita half. Fill with 2 tomato slices, 2 zucchini cakes, red onion slices, and ⅓ cup chopped lettuce. Drizzle each gyro with 2 Tbs. yogurt mixture