Preheat oven to 350°. Grease a 9? pie dish. Steam fresh spinach until just wilted. (Frozen spinach won?t need to be cooked, just thawed.) Press water out of cooked or thawed spinach and set aside. Heat oil in small skillet and cook onions until soft but not brown. Combine ricotta cheese, egg substitute, dill, pepper, and nutmeg in large bowl. Add prepared spinach, tomatoes, and onions. Mix thoroughly and tip into pie pan.
Sprinkle Parmesan cheese over the top and bake until set, about 30 minutes. Let quiche cool for 5 or 10 minutes before serving. Serves 6.