||Tzatziki: Stir the yogurt with the cucumber, vinegar, mint, dill, oil, salt and garlic. Chill for at least 2 hours.
||Sliders: Preheat the grill to medium-high; lightly coat the grate with cooking oil. Stir the breadcrumbs with 1/2 cup tzatziki, feta, lemon zest, oregano, salt, pepper, garlic and egg. Crumble in the turkey and gently mix to combine. Form into 16 patties.
||Grill, turning as needed, for 15 minutes or until well-marked and cooked through.
||Split the pitas open. Spread some tzatziki on the inside of the pita. Add lettuce, tomato, cucumber and a cooked patty.