Sicily is well-known for its bountiful seafood, which you'll often find served with a sharp and sweet vegetable stew called caponata. So, for this dish, we're going all the way south and off the toe of the boot to serve our fresh blue-eye trevalla with that saucy classic. Add a garlic-butter flatbread for scooping and you can just about smell the Mediterranean.
Preheat oven to 200°C fan-forced. Cut eggplant into 2cm pieces. Heat 20ml (1 tablespoon) oil in an ovenproof frypan over medium-high heat. Add eggplant and cook, covered and stirring occasionally, for 8 minutes or until golden brown and tender. While eggplant is cooking, continue with step 2.
Peel and cut onion into 1cm pieces. Remove core and seeds from capsicum and cut into 2cm pieces. Pick oregano leaves from their stems. Add onion, capsicum, salt and pepper to eggplant and cook, stirring, for a further 4–5 minutes or until vegetables are starting to soften.
Add chilli flakes, olives and tomatoes and bring to a simmer. Transfer to oven and cook for 15 minutes or until fragrant and reduced slightly. While caponata is cooking, continue with step 4.
Crush garlic. Place garlic and butter in a saucepan over low heat for 1–2 minutes or until melted and fragrant. Place souvlaki breads on a lined baking tray and brush with garlic butter. Sprinkle with salt and bake for 8–9 minutes or until golden and crisp.
Remove caponata from oven and stir through oregano. Sprinkle fish with salt and pepper and drizzle with remaining olive oil. Place fish, skin-side up, in caponata and return to oven for 8–9 minutes or until just cooked through.
Cut flatbreads into wedges. Divide fish and caponata between plates and serve with flatbreads.