Cream of Watercress Soup

The watercress appears at the market in thick, wet bunches around April, when the chalk streams are still cold and the leaves are dark and small and taste of iron and pepper. That's when this soup makes sense. Not the supermarket watercress in plastic bags, which is polite and mild and good enough for a sandwich. The proper bunches, dripping, with stems like wire and a bite that catches the back of your throat.

This is one of the oldest soups in the British kitchen. Hampshire claims it, and rightly. The chalk streams around Alresford have been growing watercress for centuries, and the soup that comes from it is as plain and good as anything I know. Potato for body. Onion for sweetness. Stock and cream. The watercress does everything else.

The trick, if there is one, is not to cook the watercress. It goes into the hot soup off the heat, wilts in seconds, and gets blended straight away. That's how you keep the colour vivid and the flavour sharp. Boiled watercress turns grey and sulky. Treated gently, it stays the green of something alive.

I wrote it down in the notebook years ago: watercress soup, April, the kitchen smelled like spring water. I've made it every year since, and the note still holds. There are few better feelings than putting a warm bowl of something this green in front of someone on a cold evening.