Even the dishwasher heavy cycle won't get this one clean!
When you have cemented-on grime, what can you do?
My secret: Fill with hot water and add 2-4T oxiclean versatile.
Let it sit overnight. In the morning it will look like this and will wipe clean instantly!
I have used this for the last couple of years with homemade mac n' cheese pots and have used it in both non-stick skillets and stainless steel with no ill effects. You will have to experiment with your own dishes as to whether or not it is safe for all types of pans.