Making nettle soup has been part of the spring ritual since 1972, when the Richard Mabey book 'Food for Free' was published, as a system spring clean for the changing season. This version is spruced up with horseradish and chives. The months of March or early April are the best time to make this soup, when new furry nettles are tenderly working their way through the still-cold soil. Nettles typically grow close to human activity, on waste ground, farmland or the edges of gardens – especially on nutrient-rich soils. They make a delicious hedge food when picked young and tender, selecting only the top 6-8cms of the nettle. For easy, clean picking, make sure you go out equipped with scissors and rubber gloves and avoid polluted spots. If you can’t find a piece of fresh horseradish root to grate, a teaspoon or so of a good quality horseradish sauce or prepared horseradish whipped into the crème fraiche is a good substitute.
3 banana shallots, peeled and sliced
1 clove garlic, peeled and sliced
2 medium potatoes, peeled and chopped into small cubes
700ml vegetable stock
100g (a good colander full) nettle tops, washed and rinsed well and spun dry
A handful of flat leaf parsley, toughest stalks removed and roughly chopped
4 tablespoons of crème fraiche
2 tablespoons of very finely grated horseradish
A handful of chives
1 teaspoon olive oil
Sea salt and black pepper
Serves 4 as a first course or 2 as a light supper
Melt the butter in a medium sized, heavy pan on a low heat and add the shallots and garlic. Continue to cook at a very low temperature, keeping them just bubbling away, but not browning, until very soft and fragrant, for around 10-15 minutes. Take the chopped potatoes and add to the shallots, season with salt and pepper and cook for 5 minutes more, until just beginning to soften at the edges. Then add the vegetable stock and bring to the boil, cooking until the potatoes are tender, around 15-20 minutes in all.
Whilst the potatoes are softening you can make the horseradish cream and the charred chives. Combine the grated horseradish with half of the crème fraiche and season with a little salt and pepper. Toss the chives in a very little olive oil and char in a dry frying pan, or a hot oven, until darkly green and crispy in places. Then add the nettle tops and the parsley to the soup pot and boil for a further 3-5 minutes until soft (don’t cook too long otherwise the soup will become a duller shade of green).
If you are making the soup in advance and want to retain the strong green colour you’ll need to cool the soup as quickly as possible to prevent browning. If you plan to serve the soup straight away, you can leave out this step and proceed directly to blending. Fill your sink with a few inches of cold water – enough to come up to the level of the soup in your pan. When the nettle tops are tender, quickly remove the pan from the heat and lower into the cold water and leave to cool.
Whizz up the soup with a blender until a smooth texture and return to the pan to reheat. Add the other half of the crème fraiche and a good dose of salt and pepper.
Serve topped with a spoon or two of the horseradish cream and using a pair of kitchen scissors snip over the charred chives.