"Back to the Roots" Soup

Last night, I cooked for 3 wonderful ladies (the Australian, Mademoiselle and Amica) and even though it was a work night (well, for me at least, not for my guests) I wanted to make a proper meal. This meant that I needed to go for something I could at least partly prepare the night before. I chose a cream soup for starter, something I really like in winter and apple crumble with vanilla ice cream - one of my favourite soulfood dishes for the cold months - for dessert.

The soup turned out really well if I may say so myself and I want to share the recipe with you. I actually also want to write it down to be able to recreate it soon. It was inspired by Jamie Oliver's "potato, celeriac and truffle oil soup" (out of Jamie's Kitchen), but the only thing I kept is the celeriac, thyme and truffle oil. He uses chicken stock, for example, but I don't like using meaty stock for vegetable soups and always go for (organic) vegetarian stock cubes. The thyme gives an incredibly deep flavour to the soup, even more so than the truffle oil. So here goes:

Ingredients:

1 small (white) onion - I always use shallots - diced
1 knob of butter
a bit of olive oil
1 bunch of fresh thyme, tied together with a string
500g* celeriac, peeled and roughly diced
250g* parsnips, peeled and roughly diced
250g* sweet potato, peeled and roughly diced
a little bit of white wine
1.2 l boiled water (use your kettle)
2 cubes of vegetable stock (feel free to make fresh vegetable stock if you want)
salt and freshly ground black pepper
truffle oil
125ml cream

* You can play around with the quantities of the 3 veggies according to your preferences, but try to use approx. 1 kg (unpeeled) in total.

Preparation:
In a biggish pot slowly fry the onion in the butter and olive oil until translucent and soft. Add your bunch of thyme (if you work with a gas stove be careful that the string doesn't catch fire on the open flame...) and all the diced vegetables. Turn up the heat and deglaze with the white wine. Add the boiled water and vegetable cubes, put on the lid and let simmer on a low temperature until the vegetables are soft. I usually turn off the heat after 15 minutes or so and just let the pot sit and cool down a bit for half an hour or so. Remove the bunch of thypme and purée the soup in a liquidizer or food processor until it is nice and smooth. This is what mine looked like before mixing:
Season with salt and pepper to taste and add half of the cream before reheating it for your guests. Whip the other half of the cream until it is just slightly firm, but not stiff, and gently fold under the soup just before serving. Let your guests add the truffle oil (it pays off to use a good one and make sure it is fresh - they go off quite easily) themselves. Serve with fresh bread (I used wholegrain baguette) and lick your lips.

I had the tiny leftover bowl for dinner today so am happy to report that it tastes good the day after, too.