Fill a pan with water. Add a pinch of salt. Cover. Bring to the boil. Wash the sprouts and trim off the stalky bottoms so they’re neat and flat. Pull off any torn outer leaves.
When the water’s boiling, add the sprouts. Simmer, without the lid, for 5 mins till they are just cooked but still nice and firm. Drain them.
While the sprouts simmer, roughly chop the chestnuts.
Warm a splash of olive oil in a deep frying pan or wok. When it’s hot, add the chestnuts and lardons. Stir and fry for 5-8 mins till the lardons are crisp and golden.
Add the sprouts. Stir and fry for 2-3 mins so everything is mixed through and warm. Tip into a serving dish and serve.