Sweet as a nut: New-season walnuts are creamy, delicate and a cracking ingredient for salads, meats and tarts

Autumn is the time to be on the look-out for fresh nuts, especially walnuts and the young sweet hazelnuts known as cobnuts. It doesn't surprise me that some people turn their nose up at walnuts, but I think that's because very few have access to the new season's crop. Young walnuts, known as wet walnuts, are sweet, creamy and earthy, whereas an older nut not stored properly will quickly turn rancid. Always buy nuts in their shell and store them in a cool, dark place.

The flesh of young walnuts that have just dropped from the tree is delicate and mild, and their shell still unformed enough to twist open with your hand. Eaten with cheese or tossed through salads with pears and celeriac or simply served with cured meats, they are one of the treats of early autumn. Search them out and eat them now!

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

Anchovy and walnut sauce

This lovely textural, creamy, salty sauce is perfect for all the inky green vegetables that begin to make their appearance in early autumn. This sauce is best made on the day it is to be eaten.

Makes enough for 6

2 good-quality anchovies
1 clove of garlic, peeled and finely chopped
1 small bunch of flat-leaf parsley
A handful of shelled walnuts, finely chopped
100ml/31/2fl oz extra-virgin olive oil

Pound all the ingredients except the oil in a pestle and mortar until smooth, then pour in the oil and stir well to combine. Spoon over any lightly cooked green vegetable, such as broccoli, spinach or chard.

Pappardelle with walnut and Gorgonzola sauce

This rich, indulgent sauce works well with any good-quality, egg-based pasta.

Serves 4

For the sauce

100g/31/2oz young walnuts
2 tbsp freshly grated Parmesan
1 clove of garlic, peeled and finely chopped
Sea salt and freshly ground black pepper
150ml/5fl oz double cream
50g/2oz Gorgonzola (preferably dolce, the softer milder variety)
300g/10oz pasta (I use pappardelle)

Crack the walnuts, remove the nuts from their shells and pound with a pestle and mortar until they are in small pieces. Sprinkle over the Parmesan and add the garlic. Season with plenty of black pepper and a small amount of salt. Pour in the cream and stir well to combine.

Place a large pot of well-salted water on to boil and cook the pasta following the instructions on the packet.

While the pasta is cooking, gently warm the sauce in a small saucepan. Add the Gorgonzola and stir continuously while the cheese melts. Now drain the pasta and dress with a generous knob of butter, spoon over the sauce and toss to combine. Taste and adjust the seasoning if necessary.

Walnut tart

This is a lovely, creamy and delicate tart; a drizzle of honey and perhaps a spoonful or so of crème fraîche is all that it needs.

Serves 8-10

For the pastry

250g/8oz plain flour
175g/6oz cold, unsalted butter, cut into little cubes
1 whole egg
1/2 tsp caster sugar

For the filling

300g/10oz young walnuts, pulsed
120g/4oz sugar
5 tbsp double cream
2 medium-sized eggs
A few drops of vanilla extract
30g/1oz unsalted butter, melted

Put the flour, butter and sugar into a food processor and pulse until it is the consistency of wet sand. Add the egg and blend once more; the pastry should gather itself into a ball – you may need to add a tablespoon of cold water if it looks dry. Gather up and wrap in parchment paper and place in the fridge for 30 minutes.

Heat the oven to 180C/350F/Gas4. Roll out the pastry and line a 10in tart tin. Prick with a fork, then cover the base with parchment paper and baking beans and blind-bake for 20 minutes. Remove the beans and paper and return the tart shell to the oven for five minutes to dry out the base. Remove from the oven and allow to cool. Turn up heat to 190C/375F/Gas5.

In a large bowl, combine the ground walnuts, sugar, eggs, cream and vanilla extract. Stir together well to combine and pour in the melted butter. Pour the filling into the cooked tart shell and carefully return to the oven. Bake for 25-30 minutes until the custard is golden-brown and the centre is still slightly wobbly. Remove from the oven and allow to cool a little before serving.