Peel a couple of medium-sized onions and slice them thinly.
Warm 3 tbsp of vegetable or groundnut oil in a wok or wide shallow pan over a moderate to high heat, then tip in the onions and let them cook until soft and golden. You will need to stir them, so they colour evenly. You are after a light brown tangle of very soft onions, so give them 5 minutes uncovered, then continue cooking partially covered with a lid for 15-20 minutes or so.
Meanwhile trim 300g of brussels sprouts and cut them in half. Remove the skin from 250g of spicy cooking chorizo and break into pieces about the length of a wine cork.
Add the chorizo to the onions and leave to colour lightly, then add the sprouts and toss everything to mix. Continue cooking until the sprouts are tender but retain a bit of bite, and the onions are glossy and coated in the chorizo juices.
While everything is cooking, finely chop a good handful of parsley. Turn the heat up under the pan, remove the lid and pour in 50ml of dry sherry and toss in the parsley. Let the sherry bubble for a couple of minutes, letting it mingle with the juices already in the pan, then pile into shallow bowls. Enough for 2
As always, taste for seasoning, but in this case you are unlikely to need salt and pepper – the chorizo does the seasoning for you.
Try also with sprout tops, savoy cabbage (rolled and cut like pappardelle) or chard leaves.
I sometimes do a version of this with apples fried with the sprouts, and with crumbled black pudding in place of the chorizo.
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