It's not a complicated process to caramelize onions, but it does require your full attention. Don't be alarmed by the number of onions this recipe calls for, once the onions are cooked, they reduce by three quarters: 16 cups (4 pounds) of raw onion become four cups of caramelized onion! A heavy-bottomed pan is best, it holds the heat, creates a barrier from the direct flame and cooks the onions evenly. Other uses for caramelized onions are omelets, mashed potatoes, topping a burger or sausage sandwich. Add a little vinegar and a pinch of sugar and make an onion jam! Caramelized onions freeze well. Freeze in small amounts for various uses in the future.