1 Wash the nettles, then pick them over, discarding the tough stalks. Bring a large pan of well-salted water to the boil, throw in the nettles and bring back to the boil. Blanch for a couple of minutes, then drain. When cool enough to handle, squeeze the nettles, extracting as much water as possible, and chop finely.

2 Heat the stock until almost boiling, then keep warm over a low heat.

3 In a large, heavy-based pan, melt the butter over a medium heat. Add the onion and sweat for eight to 10 minutes, until it is soft and translucent but not browned. Add the rice. Stir to coat the grains, pour in a third of the hot stock and bring to a gentle simmer. Cook, stirring, until almost all of the stock has been absorbed.

4 Add the chopped nettles and a little more stock. Keep adding stock a bit at a time, whenever the previous splash has been absorbed, until the rice is nicely al dente. (You may not need all the stock.) This should take about 20 minutes. The mixture will be loose and creamy.

5 Stir in the sorrel and season to taste.

6 Dot a little butter over the risotto and sprinkle with the cheese. Cover, leave for a few minutes, then stir in.

7 Serve straight away with more grated cheese.