Cheaper & Better by Nancy Birnes Typed for you by Nancy Coleman
Fill a shallow baking pan with ammonia and place on the top shelf of your oven. fill another pan with 2 cups boiling water and place on the bottom shelf. Close oven and leave pans in for at least 2 hours or overnight.
Remove ammonia and make a past of ammonia, baking soda and vinegar. Spread paste on oven surfaces, leave on for 15 minutes, and then scrub off with a sponge or steel wool.
Pre-heat oven to 200 degrees. Leave oven on for 15 minutes; turn off and leave the door closed.