Roasted Vegetable & Olive Frittata

Serves 8-10 as a side

8 large eggs
1 red onion, thinly sliced
1 yellow pepper, thinly sliced
1 red pepper, thinly sliced
1 courgette, sliced
2 sprigs rosemary
1 tbsp. olive oil
2 garlic cloves, crushed
100ml milk
Sea salt and ground black pepper
25g parmesan, grated
50g green olives, halved
15g fresh parsley, chopped

1. Preheat oven to 200°C / 180°C. Line a 20cm x 30cm baking tin with
greaseproof paper, making sure it hangs over the sides.
2. Add the sliced vegetables to the tin with the sprigs of rosemary. Drizzle
with olive oil then roast for 15 minutes.
3. Add the crushed garlic and continue to roast for another 10-15 minutes.
Remove from the oven and take out the sprigs of rosemary. 
4. Turn the oven temperature down to 160°C fan. In a large jug, whisk the
eggs with the milk and season with salt and black pepper, then add the
grated parmesan and chopped parsley.
5. Scatter the olives over the vegetables, then pour over the egg and milk
mixture. Bake for 30 minutes until set and lightly golden on top.
6. Leave to cool, then cut into squares and serve.