Cauliflower and celeriac soup with pistou

Ingredients 1 white onion, butter, 1 cauliflower, 1 celeriac, 1 pint vegetable stock, basil leaves, basil oil, almond slivers.

Serves: 4 Preparation: 30 minutes

I love soup. I find all the chopping, stirring and pureeing very soothing, the warm smells that fill the house comforting, and I love ladling out steamy bowls of soup for people to dunk hot crispy bread into, dressing it with ever more creative croutons or swirls of cream and yoghurt. This soup has a velvety smooth texture and a wonderful earthy flavour which is beautifully contrasted by the swirl of pistou (a French equivalent of pesto made of almonds, which are the cauliflower's perfect flavour partner).

1) Peel the celeriac with a sharp knife by cutting about a centimetre off both ends and sides, leaving a squareish core. Prepare the cauliflower by removing the leaves and slicing the stem to the base. Slice around the stem to release the florets. Dice both and set aside.

2) Peel and dice the onion and sautee in a little butter until soft. Stir in the cauliflower and celeriac, then add the vegetable stock and simmer on the hob for 20 minutes.

3) To make the pistou, add a good handful of fresh basil leaves to a mortar bowl and grind to a fine pulp. Lightly toast the almond slivers, shaking and turning the pan until they just turn golden brown, before adding to the mortar bowl with a glug of basil oil and grinding thoroughly.

4) Separate the vegetables from the liquid using a colander and puree thoroughly in a blender.

5) Pass the pureed cauliflower, celeriac and onion through a sieve and back into the stock, then stir through until the soup has been incorporated. Serve with the pistou.