Preheat the oven to 200 degrees C. Melt the butter in a large frying pan, add the vegetables then cook over a gentle heat for 2–3 minutes, stirring regularly.
Sift the flour into a bowl. In a jug, beat the milk with the eggs then gradually whisk into the flour to make a smooth batter. Season with salt and pepper.
Stir the parsley into the pan with the vegetables then spread evenly in a 1.5 litre oven-to-table baking dish and smooth level with the back of a spoon. Pour the batter slowly over the vegetables.
Bake for 35–40 minutes or until lightly set and golden. Serve hot from the baking dish, garnished with sprigs of fresh flat-leaf parsley.
This dish could also be made with diced leftover cooked vegetables. If you don't have quite enough, make up the quantity with tinned or frozen peas, carrots or corn. For individual clafoutis, bake in four small ovenproof dishes (about 400ml) and cook for 20–25 minutes until golden and set.