Lit by orange light….

I was invited to a friend’s house last night, on one condition. We had to sit in the dark. It turns out we were marking Earth Hour by eschewing electricity. I admit that our gesture of solidarity to the planet was small, but sixty minutes of candle-lit gloom became slightly addictive. Four hours later we were still sitting in the murky light shed by a dozen candles.

Although gentle candle-light is flattering to a slightly sagging complexion, it turns out that cooking in the virtual dark is a nightmare. But in the interests of Earth Hour camaraderie, I have the perfect recipe, one inspired by the great chef Skye Gyngell. It’s so easy you could make this dish with your eyes shut. And so brightly zingily fresh-tasting is it, you could light a room with its orange glow.

Oranges in Rosemary Syrup

Serves 4

5 or 6 sweet, juicy oranges. I used Maltaise sanguines, a delicious variety of blood orange

2 good sprigs of rosemary, about 10cm long

150ml light, clear honey

Cut a thin slice from the top and bottom of each orange. Stand the fruit on a chopping board and, with a very sharp knife, slice the peel off in curving downward movements. Reserve a couple of tablespoons of the juice that collects on the board as you prepare the oranges. Slice the oranges thinly and arrange on a plate.

Bend and bruise the rosemary in your hands to release the aroma and place in a small pan with the honey and the reserved orange juice. Warm gently for ten minutes over a low heat. Allow to cool for a further ten minutes, remove the rosemary and pour the honey over the sliced oranges. Decorate with another sprig of rosemary and it’s done.

After my evening of enforced gloom I walked home by the gentle light of a wind-up torch. But opening the front door was like walking into a harshly lit lift in a municipal car-park. Blinking mole-like at my slightly alarming reflection in the dazzling hallway mirror, I realised there’s another peril to entertaining by candle light. It’s impossible to see quite how many times your wine glass has been filled up.