Step 1

Whiz garlic, brioche, lemon zest, thyme, olives and 1 cup (80g) parmesan in a food processor until finely chopped. Add butter and 2 tablespoons oil, then season and pulse until the mixture resembles small crumbs. Set aside.

Step 2

Place fish on a lined baking tray and season. Press crumb mixture on top, then cover and chill for 30 minutes.

Step 3

Preheat the oven to 200°C. Cook potato in a saucepan of boiling, salted water for 10-12 minutes until tender. Drain, then mash. Beat in cream and remaining 2 tablespoons oil, then stir through remaining 1 cup (80g) parmesan. Season and keep warm.

Step 4

Meanwhile, drizzle fish with oil and bake for 8 minutes or until crust is golden and the fish is almost cooked through. Serve with mash, beans and lemon wedges.