When I went to the farm shop at the weekend to get vegetables and salad for the week I was surprised to see that they still had the knobbly but tasty Jerusalem artichokes. I usually have them as a purée but they worked so well in this earthy soup. The apple really lifts the flavour and cuts through the earthiness.

Ingredients (serves 4)

• 6 Jerusalem artichokes, peeled and sliced thinly
• 1 leek, finely sliced
• 10 portobello mushrooms, stalk removed and sliced
• 1 apple, cored and sliced
• 1 ltr vegetable stock
• Sprig of thyme, leaves only
• Seasoning to taste
• Parmesan to serve
• Whole wheat bread rolls (recipe here)
• Knob of butter and small glug of olive oil

Directions

Heat the oil and butter in a medium saucepan (the oil stops the butter burning) add the vegetables and half the apple. Cook for about 10 to 15 minutes until softened and you get a slight colour. The moisture from the mushrooms should stop anything catching.

Pour in the vegetable stock bring to the boil and simmer for 10 minutes.

Mix the thyme leaves with the apple add to the soup then blitz. Taste and season.

Serve with Parmesan and a roll.