Preheat oven to 350 degrees. Lightly grease one 9 or 10 inch pie plate or quiche pan. DO NOT use quiche pan with removable bottom. Sprinkle bacon, cheese and onion evenly in pan. Place remaining ingredients in blender in order listed. Blend on high speed for 1 minute. Pour slowly into pan over bacon mixture. Bake until golden brown crust forms or quiche and knife inserted in center comes out clean (55 to 60 minutes). Let stand 5 to 10 minutes before serving.
May substitute: 1 lb. bulk sausage, browned, crumbled and well drained
1 c. grated cheddar for 1 c. Swiss cheese (use 1 cup of both)
Use dried onion flakes, no need to saute
2 c. 1% or 2% milk instead. Can also use egg substitute for lower fat/cholesterol.