Spoon half the sauce into the base of the ovenproof dish and arrange half the roasted vegetables ... oven at 160C/140C Fan/Gas 3 for 25 minutes. Not all gruyère is vegetarian, so it's best ...

Eat the roasted vegetables hot from the oven, or allow them to cool and store in the fridge for later use. Other roast veg to include: carrots, celery, mushrooms, fennel, summer squash ...