Roasted Jerusalem Artichokes with buffalo mozzarella, roasted tomatoes and agresto

Serves 4

Serve the dish at once, while still warm (Lisa Barber)

Agresto is a soft rounded, pounded paste made with very fresh, young, creamy walnuts. It works exceptionally well with the rich, nutty flavor of roasted Jerusalem artichokes and sweet lightly roasted tomatoes.

12 Jerusalem artichokes
4 tbsp olive oil
Sea salt and freshly ground black pepper
12 little plum or cherry tomatoes
tbsp good-quality red wine vinegar
4 slices of chewy peasant style bread
1 garlic clove, peeled
Drizzle of extra virgin olive oilPinch of sea salt
Generous handful of salad leaves, such as cicorino or rocket
200g Buffalo mozzarella

For the Agresto:

20 young 'wet' walnuts in the shell
2 good-quality salted anchovy fillets
1 garlic clove, peeled
1 dried red chilli, finely chopped
1 small bunch of flat leaf parsley, leaves only, chopped
Finely grated zest and juice of 1 lemon
200ml extra virgin olive oil

First make the agresto. Crack open the walnuts (I give them a gentle tap with a rolling pin) and extract the nuts. Place a handful of them in a large mortar and start to pound gently with the pestle, gradually adding the rest of the nuts. Add the anchovies and garlic and continue to pound – the sauce should be smooth and creamy in parts, roughly textured in others. Stir in the chilli, parsley, lemon zest and juice, the gradually incorporate the extra virgin olive oil. Taste and adjust seasoning – adding a little salt if necessary and a good grinding of pepper. Set aside while you roast the artichokes.

Preheat the oven to 200C/ Gas 6. Scrub the artichokes under cold running water to remove the dirt, but don't bother to peel them. Cut in half lengthways and place in a roasting tray. Drizzle over three tablespoons of the olive oil, season generously with salt and pepper and toss to coat well. Roast on the middle shelf of the oven until the artichokes are golden brown and tender; this will take about 35 - 40 minutes.

Halfway through cooking the artichokes, place the tomatoes in a separate roasting pan, season and spoon over the wine vinegar and 1 tbsp olive oil. Roast on the top shelf of the oven for about 15 minutes until the tomatoes are soft and beginning to split from their skins. Set aside in a warm place with the artichokes while you toast the bread.

Preheat the grill and toast the slices of bread until golden brown on both sides. Once the bread is a really good colour remove from the grill and rub gently on one side with garlic. Drizzle with a little extra virgin olive oil and season with salt.

Place a slice of bruschetta on each plate. Arrange the artichokes, salad leaves and tomatoes on top and crumble over the buffalo mozzarella. Spoon on the agresto and serve at once, while still warm.

Skye Gyngell is head chef at Petersham Nurseries, Church Lane, Richmond, Surrey, tel: 020 8605 3627