I used our large master bath for this project, as I had three racks to clean. I first lined the tub with old towels so I wouldn't scratch the surface. You can see here how badly this needed done!
I filled the tub with hot water until the racks were covered and added 1/2 cup of dish soap and 6 dryer sheets right to the water.
You let this sit overnight, or for several hours during the day (I threw these in around 9am, and cleaned them around 5pm). When you pull out the racks, they will still look dirty. No worries! The gunk has been loosened so much that is literally comes off as soon as you touch it.
I grabbed the dryer sheets that had been soaking for hours and started wiping down the racks. This takes no time at all because it wipes right off. Here you can see the before and after.
After all the gunk had been wiped off, I rinsed the racks under hot water and dried them thoroughly. It was amazing to me how gross those things were!!
I cleaned my bathtub right away, and there were no scratches and no issues with staining, etc.
I tried to take an after shot of my oven, but I couldn't get a good shot without a glare and reflection from the light inside! Take my word for it, my oven looks like new again!
Check out some of my other cleaning related posts!