Many years ago, when I shared a house with a married couple, my mate's wife, Christine, showed me how to make several different things, a few of which have stuck with me over the years; braised red cabbage and red cabbage salad, the oddly named kartoffelpuffer - similar to a hash brown - and a lovely salad of chicken, walnuts, celery and apple, bound together with mayonnaise.

The other day, I poached a whole chicken for the first time in my life and immediately wondered why I hadn't done so sooner. Okay, there is no crispy chicken skin, but the offset is wonderfully moist flesh, much juicer than a roast chicken and ready in two-thirds the time. That set me thinking about the aforementioned chicken salad, how nice it would be to use poached chicken instead of roasted. All of a sudden, my mind went racing off on a tangent. Wouldn't it be great to make an autumnal soup with all those flavours?

I mean, the Spanish have a white gazpacho, made with almond meal, so for sure ground walnuts would work; apple would be easy enough to work in, but what about the celery? How about celeriac? There was just one problem, celeriac wasn't in season. Still, the idea seemed sound, so I would just have to wait. Oh, the heck with waiting, I wanted to make the soup and needed an alternative. The other day at the greengrocer, my alternative was lurking on a shelf in the shape of kohlrabi.

If celeriac isn't much used amongst home cooks, kohlrabi is used even less. A member of the cabbage family, it has a very mild cabbage flavour and would suit my purposes perfectly and after a quick session in the kitchen, a batch of soup was produced. My seven year old daughter M was asking for some lunch, so I handed her a large cup of soup. "Mmm, delicious", she said on her first taste, demolished her cup in short order and asked for another cup, then another. I had to pull her up at the third, as I needed a photo.

This soup has an intriguing flavour and none of the ingredients are readily identifiable, the walnuts gave it a smooth creamy texture without the addition of one drop of fat, the kohlrabi gave it body and the apple a little sweetness. Normally, I'm not fussed about chicken stock, happy to use stock powder or commercial chicken stock, but for this soup I strongly recommend home made chicken stock, especially one simmered with a few chicken giblets for a deeper flavour. A good home made vegetable stock would probably work well too. Really, once the stock is made, it couldn't be easier.

Walnut, Kohlrabi and Apple Soup
(serves four)

1.25 l home made chicken or vegetable stock
2 kohlrabi*, peeled and roughly chopped
2 apples, granny smith or other tart apple, peeled, cored and roughly chopped
125 g ground walnuts
salt and fresh ground pepper

Pour the chicken stock into a pot and put in the kohlrabi, apple and ground walnuts. Bring to the boil and simmer for ten or fifteen minutes until the kohlrabi and apple are tender. Pour the soup into a blender and blitz until smooth. If desired you can strain the soup to ensure no lumps, pour it back into the pot and season to taste. Serve.

*Celeriac would also be good.

This is also my entry to Kalyn's Weekend Herb Blogging, this week hosted by the lovely Anna from Morsels & Musings.