Preheat the oven to 200°C/400°F/gas ,

Put a large shallow casserole pan on a medium-high heat. Wash, trim and slice the leek (see tip) and place in the pan with 1 tablespoon of olive oil and the dried mint. Season with sea salt and black pepper, then cover and fry for 5 minutes, or until soft, stirring regularly and adding a splash of water, if needed.,

Meanwhile, coarsely grate the Cheddar and finely chop the bread to create rustic breadcrumbs, and put aside for later.,

Stir the flour into the leeks, followed by the mustard, and slowly stir in the milk to give you a loose white sauce, then add just half of the grated Cheddar and leave to blip away for a few minutes.,

Season to perfection with sea salt and black pepper, then stir in the frozen peas and broccoli.,

Snap in the pasta sheets, mix up really well to coat and separate, then pull some of the sheets to the top to create a top layer – use the back of a spoon to create some dips and wells.,

Toss the remaining Cheddar with the breadcrumbs, then scatter over. Finish with a drizzle of olive oil and bake for 20 minutes, or until golden and bubbling.,

Serve topped with an extra grating of Cheddar, if you like.