Potato Gratin

*Potato Gratin*
Serves 4

1kg potatoes, scrubbed and sliced about 1/4 inch thick
1 medium onion, peeled
2 cloves garlic, peeled & crushed
150ml double cream
100ml milk
1 teaspoon Dijon mustard (or whatever you've got in stock)
100g strong cheese (e.g. mature Cheddar), grated
Pinch of good quality salt

Place the potatoes in a pan of salted water and bring to the boil.  Cook until just beginning to soften, some 8 to 10 minutes.  Drain well.
Peel the onion and slice it in half.  Cut each half into thin slices. 

Mix the garlic, cream, milk and mustard together.  Taste and season with some salt and black pepper.

Pre-heat the oven to 200*C/400*F.  Lightly butter a shallow oven proof casserole.  Layer in the potatoes, followed by a layer of onions.  Pour some of the cream mixture over each potato layer.  Continue until all the ingredients are used, making sure there is some cream mixture left to pour over the top and making sure all the top potatoes are coated thoroughly.   Sprinkle more cheese on top if desired.

Bake for 45 minutes until the potatoes are tender, and the top of the dish is lightly browned and bubbling.