Creamy, elegant and warming, this soup makes the most of wonderful winter produce. 

serves 8

80ml olive oil

30g unsalted butter

2 leeks, remove coarse green leaves, white section washed to remove any dirt, halved lengthways, finely sliced

1 large (about 1kg) head of cauliflower, core and stem removed, broken into florets 

1 large (about 1.2kg) celeriac, peeled and roughly chopped into 2 cm chunks 

2 yukon gold or Dutch cream potatoes (approx 300g), peeled and coarsely chopped

1 litre chicken or vegetable stock

250ml milk, or almond milk

6 sprigs of fresh thyme

2 fresh bay leaves

2 teaspoon sea salt, or to taste

300g sour cream, or crème fraiche

finely grated zest of a lemon

Lemon oil

⅓ cup (80ml) extra virgin olive oil

juice from 1 lemon

leaves from 2 sprigs fresh thyme

4 whole walnuts (optional), cracked and kernels chopped

Heat oil and butter in a large saucepan over a medium heat.  Add leek, stirring to coat and cook for 10 minutes until softened, but not allowing to brown.  Finely chop the cauliflower, celeriac and potato in batches, in a food processor.  Add to the saucepan and cook for 5 minutes, stirring occasionally.

Increase heat to high and pour in the stock and milk.  Tie the thyme sprigs and bay leaves together in a bundle with kitchen string and add to the saucepan.  Add salt. Stir to combine and bring to the boil.  Reduce heat to a low simmer and cook for 25 minutes or until all vegetables are very tender.

Remove the herb bundle and discard. Stir in the sour cream and lemon zest. Using a hand held blender puree until smooth.  Season to taste, if necessary.

For the lemon oil, heat the oil in a small saucepan over a medium-high heat.  Add the thyme leaves and walnuts, if using, and cook for 1 minute.  Add the lemon juice, being careful as it will splutter and spit.  Immediately remove from heat.

To serve, ladle soup into warmed bowls.  Spoon the lemon oil and walnuts over soup.

Note: If not using straight away, store soup in an airtight container in the refrigerator for up to 5 days or freeze up to 3 months.

Fiona Hammond © July 2018 

Recipe, photos and styling by Fiona Hammond. www.fionahammondfood.com