Prepare all the ingredients.
Peel the carrots and cut diagonally into large slices.
Trim the washed courgettes and cut into 3-4 mm thick slices.
Cut the broccoli into florets. Peel the stalk with a knife and cut into slices.
Bring a pan of salted water to the boil.
Blanch the vegetables, one type at a time, (courgettes for 1 minute, carrots 4-5 minutes, broccoli with stalk 4-5 minutes) in the boiling water then cool in a bowl of iced water.
Let all the vegetables cool well.
Brush a baking dish with soft butter. Preheat the grill.
Add the mixed vegetables to the dish.
Season with salt.
Grind with pepper.
Peel the garlic and chop into fine slithers. Mix with the parsley and spread over the vegetables.
Sprinkle with the cheese.
Dot with the butter and brown under the grill for 10 minutes.
Remove from the heat and serve.