Cream of Jerusalem Artichoke Soup with Sourdough Croutons

1. Finely grate the zest from the lemon and set aside. Fill a large bowl with cold water and squeeze in the juice form half the lemon. Rinse the Jerusalem artichokes then peel them, dropping each peeled artichoke into the bowl as you go – this stops them turning brown. Remove 1 artichoke at a time from the water and roughly chop it, popping it back into the bowl and repeating until you’ve prepared them all.

2. Peel and finely chop the onions and potatoes. Peel and crush the garlic. Pop a large pan on a low heat and add 1 tbsp olive oil, the onions and potatoes. Season with a pinch of salt and pepper. Fry for 8-10 mins, stirring occasionally, till the veg are soft but not coloured. If they start to brown, turn the heat down and add a splash of water.

3. Fill and boil your kettle. When the veg are soft, add the garlic and lemon zest. Cook and stir for 1 min.

4. Drain the artichokes and add them to the pan. Pour in 1 ltr hot water from the kettle. Sprinkle in the vegetable stock powder. Drop in most of the thyme sprigs (keep a few sprigs for garnishing). Pop a lid on and simmer for 15-20 mins till the Jerusalem artichokes are soft.

5. Take the pan off the heat and remove the thyme sprigs. Squeeze in the juice from the remaining lemon half. Use a hand-held blender to whizz the soup in the pan till smooth and creamy, or ladle the soup into a blender and blend until smooth.

6. Pour the soup back into the pan, if necessary. Pour in the double cream and gently warm through. Taste the soup and add more salt and pepper, if you think it needs it.

7. Ladle into warm bowls. Drizzle with a little extra virgin olive oil, then top with a handful of croutons and a few thyme leaves to garnish. Serve straight away.