Serves 6

1 kg (2 1/4 lb) celeriac, trimmed and peeled

2 tbsp (25 g) 1 oz unsalted butter

2 tbsp plain flour (All purpose)

480 ml (16 fl oz) 2 cups milk

3 tbsp white vermouth

6 tbsp freshly grated

parmesan cheese

salt and pepper

1. Preheat the oven to 180°C (375°F) gas mark 4.

2. Cut the celeriac into thin slices and cook in boiling, salted water for about 15 minutes until tender, then drain.

3. Heat 1 tablespoon of the butter in a saucepan, add the flour and cook over a medium heat, stirring with a wooden spoon, for about 3 minutes.

4. Add the milk a little at a time, stirring continuously, until a creamy, white sauce is formed.

5. Remove from the heat, add the remaining butter, the vermouth, Parmesan cheese and salt and pepper to taste. Mix until well blended.

6. Arrange the celeriac on an ovenproof dish, cover with the sauce and cook in the oven for about 20 minutes, or until barely golden.

7. Serve immediately.