Preheat your oven to 220°C (425°F), or 200°C fan-forced.
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 well. Spread evenly.
Coat the chicken thoroughly with the remaining marinade.
Arrange the chicken on top of the vegetables in a single layer.
Roast in the oven for 28 minutes until the chicken is cooked through and potatoes are tender.
Switch to grill (broiler) for 2 minutes to crisp the edges.
Finish the Chicken Souvlaki Tray Bake with feta, herbs, olive oil, and black pepper.
Serve with pita bread, tzatziki, and lemon wedges.