In a bowl, mix baking soda with enough water to create a spreadable paste.
Spread the baking soda paste generously throughout the inside of your oven, avoiding the heating elements. Be sure to coat all surfaces, especially areas with baked-on grime.
Let the baking soda paste sit in the oven for at least 12 hours or overnight. This allows the baking soda to loosen the grime.
After soaking, use a damp cloth or sponge to wipe away as much of the baking soda paste as possible. Fill a spray bottle with white vinegar and spray down the remaining baking soda residue. The vinegar will react with the baking soda and create a foam.
0.5 cup Baking Soda
Wipe away the foamy mixture. Rinse the sponge or cloth frequently with clean water. You may need to repeat the wiping process several times to remove all the residue.
Let the oven air dry completely before using it.
Notes
For tough stains, repeat the process or use a scrubbing pad. Always test in an inconspicuous area first.