Serves 4

Week In Week Out has its own little section on kidneys called " Particular Treats". Kidneys are also one of my particular treats, especially veal kidneys. This dish, like many of Simon's, has a very old-fashioned yet modern feel about it, which is something that Simon excels at.

75g butter
3 large Spanish onions, peeled and chopped
Salt and freshly ground white pepper
50ml white wine vinegar
100ml medium dry white wine
400ml whipping cream
2 whole sprigs of sage
A few extra sage leaves, chopped
A little olive oil
2 veal kidneys, trimmed and cut into 1cm-thick slices

Melt the butter in a roomy pan and add the onions. Season and allow them to stew gently, uncovered, for at least 30 minutes, or until very soft and melting. Stir occasionally and be careful not to allow the onions to catch or colour.

Add the white wine vinegar and continue to simmer until there is no trace left of any liquid whatsoever.

Now add the wine and similarly simmer away, but this time arrest cooking a few minutes before the wine has fully evaporated. Pour in the cream and stir in the sage sprigs.

Finally, bring the mixture to its final simmer and leave to stew for about 20 minutes, stirring from time to time. Do not let the onions catch; use one of those heat-diffuser pads if you have one. Pick out the sage sprigs and discard, then stir in the extra chopped leaves. Cover the onions and keep warm. Heat a little olive oil in a heavy frying pan until almost smoking-hot. Season the slices of kidney and briefly sear on each side until golden; the entire operation – possibly in two batches – should not take much more than several minutes to achieve a nice pink interior to the kidneys.

Spoon the onions on to hot plates and lay the slices of kidney on top. Serve without delay.