cross between a roasting pan and a cookie sheet), and then,
instead of transferring everything to a stockpot, she returns the
pan—after it gets deglazed with the red wine and refilled with
the bones and water—covered with parchment and aluminum
foil to a 300°F oven and leaves it overnight to cook. If you have
a hotel pan, this method will result in a more even stock (with
fewer impurities because of the consistent temperature).
Burnt bones will give your stock a bitter flavor, which won’t be
good.
If you let it get too hot, the stock will turn cloudy and murky.
You don’t want that.