- 1 leek
- 1 onion
- 2 garlic cloves
- 200g cavolo nero
- 100g mature cheddar
- 30g plain flour
- 400ml full cream milk
- 500g potatoes
- 1 tbsp balsamic vinegar
- 250g cherry vine tomatoes
- 50g peppery salad mix
Prep: 15 mins | Cook: 40 mins
1. Preheat your oven to 200°C/Fan 180°C/Gas 6. Fill a large pan with boiling water, pop it on a high heat and return the water to a simmer.
2. Meanwhile, trim the root and woody greens off the leek. Rinse out any grit, then finely slice the leek. Peel the onion and finely slice it. Peel the garlic cloves and finely chop or grate them. Trim any dry ends off the cavolo nero. Finely shred the leaves. Pop the cavolo nero into a bowl and grate the cheddar into a bowl.
3. Pour 1 tbsp olive oil into a large pan and warm over a medium heat. Slide in the chopped leek, onion and garlic. Season with a little salt and pepper. Fry for 5-8 mins, stirring occasionally, till the veg have started to soften.
4. Meanwhile, scrub the potatoes. Slice as thinly as possible into rounds. Slide the sliced spuds into the pan of simmering water. Cook for 3-4 mins, till slightly softened but still holding their shape. Drain the potatoes and tip them into an ovenproof dish.
5. Tip the flour into the pan. Cook and stir for 2 mins to coat the veg. Measure out 400ml of the milk, then pour a quarter of the milk into the pan and stir till the sauce becomes thick and smooth. Slowly pour in the remaining milk, stirring continuously. Bring to a simmer.
6. Add the cheddar and cavolo nero leaves to the simmering milk sauce. Add a pinch of salt and pepper. Stir till the cheddar has melted. Pour the cheese sauce over the potatoes, and turn everything till coated. Slide into the oven and bake for 25 mins, till golden and bubbling.
7. While the gratin bakes, pour 1 tbsp oil into a small bowl. Whisk in 1 tbsp balsamic vinegar and a little salt and pepper to form a dressing. Chop the cherry tomatoes in half and slide into a salad bowl. Scatter the peppery leaves on top but don't toss in the dressing just yet
8. When the gratin is ready, take it out of the oven and let it cool for a few mins. Toss the salad with the dressing. Serve the cheesy gratin with the salad on the side.