I know there's already a ton of discussion on this but i'm just starting a new one bc i'm lazy.
melted butter and added flour to make roux. cooked the for a little bit then added milk slowly. stirred occasionally until thickened. took it off the heat and stirred in shredded, mozzarella and cheddar. at the end i decided to add in a slice of lowfat swiss cheese and regular american.
the sauce thickened. i poured it on top of macaroni that was drained and put back in pan which was off heat. had cooled off a bit waiting for the sauce.
mixed a bit and noticed the sauce had separated. could it have been the swiss cheese i added in the end? i know sliced cheese sometimes has added something or another to keep from sticking. the american cheese?