Chilled potato soup with watercress pesto and goats' cheese cream crostini

Ingredients

For the soup
2 tbsp olive oil
2 leeks, white and pale green parts only, sliced
2 onions, finely chopped
2 cloves garlic, finely chopped
½ tsp soft thyme leaves
4 King Edward potatoes, peeled and cubed
1 bay leaf
2 litres/3½ pints chicken or vegetable stock
pinch freshly grated nutmeg
salt and freshly ground white pepper
300ml/10fl oz double cream
3 tbsp snipped chives
For the goats' cheese crostini
1 baguette
3 tbsp extra virgin olive oil
1 clove garlic, peeled
125g/4½oz very soft, young goats' cheese
3 tbsp double cream
salt and freshly ground black pepper
For the watercress pesto
2 cloves garlic
1 tsp Maldon sea salt
large bunch watercress, chopped
5 tbsp olive oil
4 tbsp freshly grated parmesan
lemon juice, to taste
salt and freshly ground black pepper

Method

1. Preheat the oven to 160C/325F/Gas 3.
2. Heat the olive oil in a saucepan, add the leeks, onions, garlic and thyme, and cook over a moderate heat for 15 minutes or until the vegetables are soft but not coloured.
3. Add the potatoes and bay leaf and cook until the potatoes start to stick to the bottom of the pan.
4. Add the stock and nutmeg and stir. Bring to the boil, then reduce the heat and simmer for 15-20 minutes or until the potatoes are cooked.
5. Allow to cool slightly, then purée the soup in a blender until smooth, then pass through a fine sieve into a clean saucepan. Season to taste with salt and freshly ground white pepper. Thin down with more stock, if necessary. Allow the soup to cool, then chill in the fridge.
6. For the crostini, slice the baguette on the diagonal into 5-10mm/¼-½in slices. Use 2 tbsp of the olive oil to brush over the slices, then place them on a baking tray and bake in the oven until crisp and golden, turning halfway through.
7. Remove from the oven and rub each slice with the garlic clove to flavour. Set aside.
8. Place the goats' cheese in a bowl with the double cream and remaining olive oil. Mash to combine, then season with salt and freshly ground black pepper. Refrigerate until half an hour before use.
9. To make the pesto, crush the garlic cloves with the sea salt in a mini food processor until you have a fine paste. Add a little of the watercress and work together vigorously, then stir in the olive oil, parmesan and remaining watercress. Add lemon juice and season with salt and freshly ground black pepper to taste.
10. To serve, stir the double cream into the soup, then fold in the chives and top with the watercress pesto. Spread the goats' cheese mixture on the crostini and serve on the side.