There was some wonderful produce in the local farmers’ market in Twickenham yesterday. I often go with the intention of buying some particular things – yesterday I wanted to buy a couple of chickens – but it’s also great to just look around and see what’s on offer and in season. I wanted to make more soup for my freezer now that the colder weather is here as it’s great to be able to pull a portion out to defrost for lunch during the week when I’m working. When I saw some globes of creamy-green celeriac, I decided that would make a very nice soup.

It has to be said that celeriac isn’t a very pretty vegetable and getting inside to the creamy interior is a slight challenge. There’s no point in trying to use a vegetable peeler; you just need to slice the outside off with a sharp knife. It makes a wonderful classic French salad – Remoulade de Celeri-Rave – and in the winter I like to cook it and combine it with equal parts of potato, some butter, cream and black pepper to make a puree to serve as a side dish with a rich beef stew. When thinking about my soup I decided to add some potato for texture and to soften the strong celeriac taste and went for a 2:1 ratio – twice as much celeriac as potato. I considered using mustard as a flavouring thinking about the lovely mustard dressing in the Remoulade but in the end went for the less pungent choice of some fennel seeds.

My celeriac weighed just over 400g once I’d peeled it and a large potato I had about 200g. I peeled both and chopped into large pieces. But first of all I finely sliced a large shallot and slowly softened that in a large pan with some olive oil (about 1-2 tablespoons) and a large nut of butter (about 1 tablespoon). I added 1 stick of celery, sliced into smallish pieces and 1 teaspoon fennel seeds crushed.

I let them sweat in the pan for a couple of minutes until the shallot and celery were starting to soften then added the chunks of celeriac and potato. I added some salt and pepper and stirred round, then allowed it all to cook for a bit, without browning, for a deeper flavour before adding the stock.

I had some stock on the go. I’d already jointed a chicken (for Sunday evening’s meal) – according to Jonathan’s instructions – and put the carcass and trimmings into a large stock pan with onion, carrot, salt and peppercorns. It had been bubbling away nicely for a while and once my celeriac was very slightly coloured, I added some ladlefuls of the stock to the soup pan (about 700ml). I brought it all to the boil again and then turned the heat down, put a lid on the pan, and left it to simmer for about half an hour.

I checked the vegetables were cooked by squashing them against the side of the saucepan with a wooden spoon. Then I turned off the heat and blitzed it with a hand blender until nice and smooth and wonderfully creamy. I thought it was a little too thick so added another couple of ladles of stock. Then you need to check the seasoning.

I served the soup with a little cream and chopped flat-leaf parsley on the top. This wasn’t so much a pretty decoration but because both cream and parsley go so well with celeriac. However, I didn’t want to add a lot of cream and parsley to the whole pan of soup as I was planning to freeze portions and I felt it was best to add them at the point of serving.

It was very delicious and has such an earthy, nutty flavour that it feels just right for winter. Celeriac is highly aromatic but slightly more mellow than celery. Its creamy interior seems to invite you to add some more cream and that makes it a wonderfully luxurious soup that would grace a dinner party table as a starter, but I shall just enjoy rather luxurious lunches for a few days!