Combine water, salt and masa in 2 quart pan. Bring to boil, stirring constantly. Add onions, heat. Reduce heat to low and cook until it is very thick. Remove from heat. Gradually add eggs, mixing well. Add all the rest of the ingredients except 1/2 cup cheese. Mix well.

Bake in greased 9 inch pie plate at 350 degrees for 40 minutes. Sprinkle remaining cheese on top, bake 2 minutes. Serve pie shaped wedges topped with shredded lettuce, chopped tomatoes, guacamole, salsa and sour cream, if desired.