Preheat oven to 220°C (425°F).
In a bowl, mix all marinade ingredients until well combined.
Place potatoes, onion, and capsicum in a large baking tray. Add 1 tablespoon of marinade and toss. Spread evenly.
Coat the chicken with remaining marinade.
Arrange chicken on top of vegetables in a single layer.
Roast for 28 minutes until chicken is cooked and potatoes are tender.
Broil for 2 minutes to crisp edges.
Finish with feta, dill, olive oil drizzle, and black pepper.
Serve your Chicken Souvlaki Tray Bake with pita, tzatziki, and lemon wedges.