Grease a medium size casserole dish. Peel the onions, cut in half then slice thinly and layer into the cooking dish. Spread the cheese across the top of onions and bake in a moderate oven until golden and crispy - about 20 mins.
Altered ingredient amounts.
I mixed in about 2 tblsp Sage with 3 tblsp melted butter and drizzled over the top of the cheese before baking.
This one can be prepared well ahead of time also. - 19 Dec 2008