Beet and Red Cabbage Borscht
Alison Attenborough and Jamie Kimm always make borscht around the holidays. One year, they had roasted fennel left over after a day of food styling and decided to add it to the soup pot; they've been making borscht with fennel ever since. They like their soup really sweet and sour, but you can adjust the vinegar and honey to your taste.
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