1

Bring a large pan of water to a boil and cook the cauliflower, broccoli and carrot for 6 minutes, adding the leek for the final minute. Drain and set aside.

2

Preheat the oven to 190°C, fan 170°C, gas mark 5. Melt the spread in a large pan over a medium heat, then add the garlic and mustard. Stir in the flour and cook for 1 minute, then whisk in a little of the milk until smooth. Gradually whisk in the remaining milk, bring to a simmer and cook, stirring, for 2 minutes until the sauce is thick enough to coat the back of a spoon.

3

Add most of cheese, then season to taste and stir to melt. Remove from the heat, add the boiled vegetables and stir to combine.

4

Transfer the cheese and veg mixture to a 2.5-litre baking dish. In a small bowl, combine the breadcrumbs, olive oil and chives, then scatter over the veg. Sprinkle over the remaining cheese. Bake for 25 minutes until golden and bubbling. Toss the salad leaves and lemon juice together, then serve the veg bake with the salad on the side.