1. Preheat the oven to 220 °C (425 °F). Place rack in centre of oven. Line a baking sheet with parchment paper (or a reusable baking mat).
2. Cut onion in half and thinly slice.
3. Place onion, beans, tomatoes and olives on baking sheet. Add 7.5 mL (½ tbsp.) oil and mix to coat vegetables. Generously season with pepper.
4. Move vegetables to the edges of the sheet to free up space in the middle.
5. Place trout in the centre of the baking sheet. Brush fish with remaining oil (7.5 mL/½ tbsp.) using a pastry brush. Season generously with pepper and add a pinch of salt.
6. Slice lemon half into rounds and spread over fish.
7. Bake in the oven for 15–20 minutes or until fish flakes easily with a fork.
8. Serve with fresh bread.

Photo credit: Sylvie Li