Don't be fooled by the
simple-sounding recipe title or the
short list of ingredients. Magic
happens when onions are cooked
slowly in bacon fat. Even a basic,
sharply flavored yellow onion
becomes lusciously mellow after a
long, slow cooking, but if you are
able to find innately sweet onions
at the market, like Vidalias, then
this tart will have an
incomparable, complex smoky and
honeyed flavor.