C.M.
I would either try a magic eraser or this recipe I found on the internet. Good luck!
Water
3 tablespoons of sugar
Detergent
A sponge/cloth (a scrubbing brush is advisable in substitution of cloth)
How to make it work:
Take those greasy pot/pans and lay them on a flat surface.
Add 3 tablespoons of sugar to the base of the pot/pan.
Add a small amount of detergent.
Add some water (measurements are not necessary).
Rub the mixture around the pot/pan using your sponge/cloth until it appears that the grease has been removed.
Poor away the mixture (and the grease).
Rinse the pot/pan.
If any residue remains, simply repeat the process with smaller measurements of sugar and detergent.