Note: According to Mimi Sheraton's classic

"When cooked properly red cabbage is known as Blaukraut - blue cabbage - because of the deep purple color it takes on. This is due to the hot vinegar
and fat in which cabbage is braised before before water or stock is added.
If you skip that initial step, the cabbage will 'bleed' as it cooks and you
will have the faded pink oversoft concoction that gives red cabbage a bad
name. It tastes best when made a day in advance."

Remove any spotted or ragged outer leaves from cabbage. Cut it into
quarters, wash and drain. Shred the cabbage on a mandoline or similar
slicing instrument, discarding core and tough ribs. Heat fat in a large
stainless steel or enameled Dutch oven. (If using bacon, do not let it
brown.) Add sugar to hot fat and sauté slowly until golden. Add onion
and apple, cover pot and braise over very low heat 2 minutes. Add the
shredded cabbage and toss until it is coated with fat. Pour vinegar over
mixture and stir well to mix. Cover pot and braise slowly over low heat
about 10 minutes or until cabbage has turned "blue" (actually bright
purple). Add the stock, red wine and cheesecloth bag. Cover pot and
bring liquid to a boil. Reduce heat to low and simmer 1 1/2 to 2 hours
or until cabbage is very tender. Check seasoning for salt (depending on
saltiness of stock and whether you are using bacon). Thicken with
beurre manié made by kneading together 2 tablespoons each butter
and flour. Simmer 3 to 4 minutes, or until thickened. (Alternatively,
mixture can be thickened by sprinkling 2 to 3 tablespoons flour over
the cabbage mixture and stirring a few minutes until it is thickened.)
Serves 6.

(Note: Many German recipes call for the addition of 1/4 cup red currant
jelly stirred in just before serving, in which case reduce the amount of
sugar used in the initial braising. Excellent with Sauerbraten and
Kartoffel Kloesse!)