I don’t know how anyone else makes it, but mine comes out almost like a pareve quiche. Preheat the oven to 350 degree.
You slice up and saute two really large onions, along with a can of mushroom pieces until all are soft and a little browned. Drain off the oil and add 1/2 cup of mayo, 4-5 eggs, 1 1/2 – 2 tsp. salt and a good shake of black pepoer. Put in a Pam-sprayed 9″ square disposable pan, and bake at 350 degrees until the top looks golden brown and feels firm to the touch (almost spongy). I check after a half hour to see if it has baked enough.