BAR KEEPERS FRIEND when I got some new Calphalon pans (actually warranty replacements) a few months ago, they all seem to come with a little pushy package inside. A small envelope filled with a powdery substance, claiming to be this cleaner called Bar Keeper’s Friend. Calphalon was including it as a sample in all their new packages because apparently it was great at cleaning the outside of Calphalon pans from stains, burn marks, etc. Not a bad promotional idea. I read the side of the envelope several times, and it touted BKF as being the be-all end-all for cleaning surfaces such as stainless steel, porcelain, counters etc. I’d heard of B. KF that kind of petered out after several decades and still stood like the haunting toast of antique brands past someone a few shelves below Comet at the supermarket. Even the package design is old-fashioned — but I guess…