Hi, Pete,
Use Easy Off Oven cleaner, ware your glove and eye protector.
After you spray, it will turn "black", do not worry it is O.K. It only takes 3 to 5 min. to take off anodized finish, use prenty of warm water to wash off, and use Mother's Aluminum Polish to finish up, it will shine like a mirror finish. I have done 3 times in this way.
KEN TODA, High Point, NC, 20 minutes away from our Webmaster!