- 50g butter
- 1 celeriac, peeled and cubed
- 1 potato, peeled and cubed
- 1 leek, trimmed, washed and roughly sliced
- 1 onion, peeled and roughly chopped
- 1 garlic clove, sliced
- 1 litre stock, chicken, vegetable or made from the bones of your Christmas bird
- Melt the butter in a large, heavy-based pot over a medium-low heat. Add the celeriac, leek, potato, garlic and onion, season generously, and gently sweat the vegetables until they're all starting to soften (this will take about 10 minutes).
- Add the stock, bring the soup up to a boil, turn down the heat and simmer for about 20 minutes or until the celeriac is completely tender. Liquidise until smooth, return to the pan and reheat over a medium flame. Just before serving, check the soup for seasoning and serve.