Cook onions in oil until golden brown: wash zucchini. trim ends and slice thin: add to onions and cook over medium heat until soft and lightly browned (about 15 minutes). Remove to a bowl. draining oil.
Beat eggs slightly: add cheese and drained zucchini mixture after it has cooled slightly. Mix well and add remaining ingredients.
Melt butter in 10 inch fry pan & pour in zucchini mixture. turning heat as low as possible. Cover and cook until set (about ½ hour). Before serving. put uncovered under pre-heated broiler just to brown top.
