Preheat the oven to 200 °C (180 °C fan). Wash and prepare the courgette, pepper and onion and cut them into large pieces.
Put the veg in a baking dish. Strip the rosemary from the sprigs and mix it into the veg with the olive oil, salt and pepper.
Make a little space in the middle and lay the feta in as a whole block. Drizzle the feta with a little olive oil.
Bake everything at 200 °C for 20–25 minutes, until the veg is soft and slightly roasted at the edges. The feta should become warm, soft and slightly creamy.
Briefly take the dish out of the oven and carefully turn the veg once if you'd like more roasted flavour. If needed, bake for a few more minutes at 200 °C.
Serve straight from the dish, pressing the soft feta lightly into the veg so everything comes together.
Good to know
A dish like this is little work and still feels like a proper meal. In the oven everything turns soft, aromatic and wonderfully juicy.
Swaps
Feta → goat's cheese (often a little stronger in flavour, also provides protein and calcium); courgette → aubergine (also provides fibre); pepper → cherry tomatoes (also provide vitamin C, plus lycopene); olive oil → avocado oil (heat-stable, mainly monounsaturated fats)
Allergens
Contains milk (feta); usually good for children if seasoned moderately, and generally suitable in pregnancy as long as the feta is made from pasteurised milk.