Nanaimo Bars are a layered bar cookie named after a small town in British Columbia, Canada. The bottom layer of graham cracker or wafer crumbs, butter, coconut and nuts is topped by a vanilla butter cream icing (made with Bird's Instant Custard, for Brits or Canadians, Instant Pudding for Americans), itself topped with a layer of dark melted chocolate. The seem to have been the creation of a woman named Mabel Jenkins, from Cowichan Bay. Ms. Jenkins submitted the recipe to the Ladysmith and Cowichan Womens' Institute Cookbook, a charity cookbook that became very popular in the region. The cookbook, and the cookies, were popularized elsewhere in rapid order. The best discussion of the Nanaimo bar history is on Wikipedia. The City of Nanaimo in a burst of civic pride has encouraged the spread of the cookie, and their name, and even held a contest for the best recipe.

There's a thorough discussion of the method and a Nanaimo Bar recipe at Joy of Baking. A Pacific Northwest newspaper just across the border in Washington offers a more straight forward recipe here (scroll down a bit). This Nanaimo Bar recipe is the original that appeared in the Women's Institute Cookbook

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