spaghetti with carmelized onions and spinach

for whatever reason, caramelized onions have been sounding divine to me lately...perhaps because it is vidalia onion season and i am having a bit of nostalgia for sweet ol' georgia.  and, i just love the aroma they fill your house jack says, "mmmmm!" spaghetti with caramelized onions and spinach

adapted from dinner: a love story

pour a few glugs of olive oil into a skillet set over medium-low heat, and cook 3 large onions (sliced) for a minimum of 15 minutes and up to 45 minutes. while the onions cook, prepare 1/2 pound spaghetti according to package directions. during the last minute of pasta cooking, add a handful of frozen spinach to the water.  drain pasta and spinach together.  toss pasta and spinach with olive oil and distribute into bowls.  stir about a tablespoon of balsamic vinegar into the onions, then heap the onions on top of the pasta. top with freshly grated parmesan cheese.