First, make a sauce by melting the butter, blending in the flour and stirring in the milk gradually and cooking together.
Season to taste.
Mix together the onion, parsley, seasoning, cheese and 1 oz.
butter and nutmeg.
Peel and slice 11/2 lbs. potatoes thinly.
Put a layer in an over-dish, which is well greased.
Then add half the onion mixture (Also some sliced tomatoes, but this is optional).
Then more sliced potatoes and after that more onion mixture, finishing off with sliced potatoes.
Pour over the sauce and bake for 45-50 minutes in a moderate oven.