Preheat the oven to 200°C / 180°C fan.
Chop the mushroom into thin slices and the cherry tomatoes in half. Set aside for later.
Roughly chop the onion, courgette and red pepper. Place them on a baking tray and drizzle with the olive oil and a little salt and pepper. Bake for 30 minutes.
Remove veg from oven and reduce temperature to 180°C / 160°C fan.
Grease and line a large tin or dish of choice. I used a 9" round tin.
Place your baked vegetables into the bottom of the tin/dish, followed by the raw cherry tomatoes.
In a bowl, beat the eggs, milk, cheese, chopped chives, salt and pepper.
Pour the egg mixture over the vegetables in the tin.
Place your mushroom slices on top.
Bake for 30-40 minutes or until set in the middle and golden on top. If it starts to brown too much, cover loosely with foil.
Allow to cool for 5-10 mins before slicing.