The Easiest Way to Clean Your Oven Window (Seriously!)

Preheat the Oven: Begin by preheating your oven to 150°F (or the lowest temperature setting available). This gentle warmth helps activate the cleaning process without baking anything onto the surface.
Prepare the Steam: While the oven is heating, place a pot of water on the stovetop and bring it to a full boil.
Set Up the Oven: Once the oven reaches 150°F, turn it off. Carefully pour 1 cup of ammonia into a heat-safe bowl or baking dish and place it on the top rack of the oven.
Add the Boiling Water: Place the pot of boiling water on the bottom rack of the oven. Immediately close the oven door to trap the heat and steam inside.
Leave Overnight: Leave the oven closed overnight. The combination of steam and ammonia fumes works to soften baked-on grease and grime on the oven walls and glass.

Cleaning the Next Morning

Ventilate: The next morning, open the oven door and carefully remove the bowl of ammonia and the pot of water. Keep the ammonia — you’ll use it again. Remove the oven racks and leave the oven door open for about 15 minutes to allow fresh air to circulate.
Mix the Cleaner: Add 1–2 teaspoons of dishwashing liquid to the reserved ammonia, along with 4 cups of warm water. Stir gently to combine.
Wipe Away Grime: Wearing kitchen gloves, dip a heavy-duty nylon scrubbing pad into the ammonia mixture and begin wiping the inside of the oven, including the sides, bottom, and oven window. The grease and residue should come off easily with minimal effort.
Rinse: Finish by wiping everything down with a clean, damp cloth to remove any remaining cleaner and residue.