Chestnut and Potato Gratin

If you can't find cantal cheese for the topping, Cheddar is good. This gratin is delicious with roast meats.

Preparation time :	30 minutes (more if using fresh chestnuts)
Cooking time :	30 minutes
Total time :	1 hour

Serves: 4

Ingredients

500g potatoes
175-250ml milk
400g fresh or vacuum-packed chestnuts
25g unsalted butter
salt
freshly ground black pepper
100g cantal or Cheddar cheese, grated

Method

1. Butter a 2.5 litre gratin dish and preheat the oven to 190°C/gas mark 5. Cut the potatoes into chunks and cook in boiling water until soft. Drain, cool slightly, then remove the skins. Meanwhile, heat 100ml of the milk until steaming. Mash the potatoes with the milk until smooth. Add more milk if necessary.
2. If you're using fresh chestnuts, make a circular incision around each of them with a sharp knife, then add to a pan of boiling water and cook for 5 minutes. Drain and peel off the skins while the chestnuts are still hot (you might want to wear gloves).
3. If you're using vacuum-packed chestnuts, skip this step.
4. Mash the peeled chestnuts with about 75ml hot milk until smooth. Beat with the potato purée, along with the butter and lots of seasoning.
5. Fill the gratin dish with the mixture and sprinkle with the grated cheese. Bake for about 30 minutes or until golden brown on top. Serve hot.