Ingredient Substitutions: You can use turkey breast or even tofu for a vegetarian option. Try swapping out the veggies for any fresh produce you have on hand. Optional Variations: Add feta cheese for an extra layer of flavor or incorporate roasted red peppers for a sweet twist. Storage or Reheating Tips: Store leftover chicken and toppings separately in airtight containers in the refrigerator. Reheat the chicken in a skillet over medium heat, and enjoy the gyros cold or warm.