Another friend of the princess said her appetite had deteriorated so much that when she ate a jam tart at Sandringham on Sunday, it was cause for celebration.

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This tart-sweet jam is a fantastic way to use apples, especially those with pink flesh.

WSJ: Gourmet Spreads

Tart-skinned green or yellow plum varieties are best for this jam, which pairs beautifully with hard sharp cheese.

WSJ: Gourmet Spreads