Put the corn cobs in a soup pot and any of the optional additions in a stockpot and add 3 quarts water. Bring the water to a boil over high heat. Reduce the heat to maintain a simmer and cook the cobs for about 1 hour, until the liquid has reduced by half and the stock is golden and flavorful. Turn off the heat. Remove the corn cobs from the stock. For a clearer stock, strain it through a fine mesh strainer.
Use immediately or, when cooled, keep covered in the refrigerator for up to 1 week or in the freezer for up to several months.
