In Food and Cooking in Victorian England: A History, Andrea Bloomfield explains the tradition of eating plum pudding on Christmas originated with a Roman Catholic Church decree to make a 13 ingredient-pudding to represent Christ and the apostles. Stir It Up Sunday hearkens to that time, too — family members took turns stirring the pudding from east to west to commemorate the Magi's journey. "Plum" once denoted any dried fruit, as reflected by Victorian pudding recipes, which included raisins, currants, beef suet, citrus zest, almonds, and spices — but not plums (or even prunes!).
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