Thursday, March 15, 2018

How to make the perfect broccoli and stilton soup

So entrenched is broccoli and stilton in my canon of classic soups – well up there with the likes of tomato, minestrone and chicken broth – that I'm slightly taken aback not to find it in Lindsey Bareham's comprehensive collection A Celebration of Soup, or indeed in any of the other books I have on the subject. The vegetable section yields similarly slim pickings, with not even a passing mention in Nigel Slater's Tender, and nary a sniff in Jane Grigson's Vegetable Book, either.

Broccoli and cheddar soup is relatively common in the United States, but I wonder whether the stilton number was popularised by the New Covent Garden Soup Company, which burst on to the market in the late 80s with soup that didn't come in a tin, and certainly not in oxtail flavour. Its broccoli and stilton version made quite an impression on me as a child. Whoever's responsible, it's a stroke of creative genius – the rich, salty cheese bringing out the pleasingly bittersweet flavour of the broccoli – and the perfect final destination for any odds and ends of stilton that might be lingering after Christmas. Vegetable soup is very January.

Vegetables
Nigella Lawson uses “frozen broccoli; actually, frozen organic broccoli, if that makes you feel better. In fact, this is better when made with frozen, and more convenient for an impromptu standby.” As someone with severely limited freezer space, frozen broccoli is a new one on me, and though it does cook more quickly, I don't think the flavour's quite up to scratch. Frozen might pass muster in a supporting role, but here, I'd strongly advise sticking with fresh.

Don't discard the stalk, as chef Sally Abé of the Harwood Arms seems to, but do add it before the florets, as Caroline Hire's recipe for BBC Good Food magazine recommends, so it has the chance to soften properly. It's all going to be pureed, but overcooked florets seem to taste mushy.

Lawson's is the only recipe that doesn't read as if it's been written in a time of severe brassica shortage: you need enough of the stuff to balance the richness of the cheese, so be generous, it's not particularly expensive at this time of year.

Hire also adds celery, leek and potato to her soup, giving it a hearty texture but a more generic vegetable flavour that detracts from the broccoli itself. That said, blue cheese has a natural affinity with the sweetness of alliums, whether shallots, as Abé suggests, spring onions and garlic, as in Lawson's recipe, or plain old yellow onions, as in Hire and Brian Turner's versions, though I'd choose shallots, the sweetest of the bunch, for preference. Whatever you use, soften them slowly in butter to help bring out this quality.

The cheese
This soup would work with just about any blue cheese, though you might need to adjust the quantity to achieve the same effect with milder, creamier varieties. A thrifty friend offers a tip about freezing the ends of blue cheese as one might do with parmesan rinds, then deploying them to add extra flavour (note, she cuts off the rind before consigning them to the freezer, which seems wise), and fishes them out before serving.

The liquid
Lawson makes her soup with vegetable stock; Abé, Turner and Hire use chicken, but I'm intrigued by a leek and stilton recipe of Mary Berry's that has a white sauce base, thinned with a little stock, variety unspecified. However, because – unlike Berry – I'll be pureeing mine. I don't think it needs thickening with flour, or Hire's potato. Milk gives the dish a more neutral base than stock alone, which can, particularly if you use good stuff, be rather rich.

Abé and Turner, with cheffy disregard for waistlines, stir in a large glug of double cream, with the latter whisking in an egg yolk, too – delicious if you're intending to serve this in tiny elegant portions for a dinner party, but it does preclude consumption in the kind of quantities I like with this soup.

Aromatics and garnish
Berry infuses the milk with nutmeg and bay leaf. As with Lawson's thyme, the bay doesn't come through, but a sprinkle of nutmeg – always a good friend to blue cheese – proves an excellent idea for a garnish: better than red chilli or chives, which look prettier than they taste. This is a dish that chooses comfort over style. And sometimes, in the depths of winter, that's just what you need.

Perfect broccoli and stilton soup(Serves 4)

2 tbsp butter
2 shallots or 1 small onion, finely chopped
800ml chicken or vegetable stock
600ml milk
800g broccoli
200g stilton, crumbled
Nutmeg, to garnish

Melt the butter in a large saucepan over a medium-low heat and add the shallots. Fry gently until soft and golden.

Meanwhile, cut the broccoli stalks into smallish chunks, then add to the pan with the softened shallots, fry for a minute, then pour in the stock and milk. Bring to a simmer, then cook until the stalk is beginning to soften (how long will depend on the size). Meanwhile, cut the head into small individual florets.

Once the stalk is almost tender, add the florets to the pan along with most of the Stilton, keeping a little back for garnish. Stir well, bring to a simmer, cover then cook for about 5 minutes, until the cheese has melted and the florets are soft.

Allow to cool slightly, then puree until smooth. Taste and season if necessary, then divide between bowls and top with the remaining cheese and a good grating of nutmeg.