> can only see tarar sauce in supermarket and im sure it cant be that
Could be a spelling issue?! :)
Cream of
tartar can be found in the baking area of the supermarket and is often a key ingredient in baking powder. It is the common name for potassium hydrogen tartrate, an acid salt that has a number of uses in cooking but can also be used to clean brass and copper cookware!! Gotta love the versatility of things like this, bicarbonate of soda, vinegar etc - all the things my grandmother would have used to both cook
and clean with...
Tartare Sauce - a whole other thing and usually eaten with fish. Mayonnaise base with capers and gherkins. Yum :)
Edited to say: a friend of mine used to use bicarbonate of soda with lemon juice to remove stains on her teeth caused by smoking and drinking. Do you think this might have been what your friend meant? See Arm and Hammer toothpaste - similar formula