Pommes Lyonnaise - cooking recipe

Ingredients

1 oz. butter, softened
1 large onion, finely chopped
2 lb. potatoes, peeled and sliced thinly
3/4 lb. Gruyere/Emmenthaler cheese, grated
1/2 pt. fresh cream
salt and pepper

Preparation

Brush base and sides of a large casserole dish with some of the butter.
Make 3 layers, each using some of the following:
potato slices (overlapping), spots of butter, onion, cheese, salt and pepper and the cream, in this order.
Cover with a lid or buttered greaseproof paper/foil.
Bake at 190\u00b0C for 1 1/2 hours.
Dish should be bubbling.
Pierce potatoes at top.
Transfer to grill for 5 minutes to brown cheese at top.