Potato and mushroom gratin

Here's an interesting twist to breathe new life into an old favourite ... a little white wine in a milky potato gratin. Gives the sweetness of the milk a sophisticated twist. Nigella's idea, unsurprisingly. Here's my version:

Potato and mushroom gratin

1kg thinly sliced floury potatoes
500 ml milk
100 ml white wine
a large handful of dried mushrooms
garlic, butter and oil

Turn the oven on to 200C.

Soak the mushrooms in a little boiling water. Put the sliced potatoes, milk and wine in a saucepan and bring to a simmer. Melt a little butter with some oil in a frying pan. Finely chop a couple of cloves of garlic and add them to the pan. Drain the mushrooms (you can add the water to the potatoes if you like) and mix into the garlicky buttery oily mess. Keep on a very gentle heat for a few minutes, stopping before the garlic browns. Mix the mushrooms in with the potatoes, turn everything out into an oiled gratin dish and bake in a hot oven for 45-60 minutes.