Here's Wikipedia's entry about the origin and history of the Nanaimo Bar:
"The bar originated in Ladysmith south of Nanaimo in the early 1950s. A local housewife from Cowichan Bay, by the name of Mabel Jenkins, submitted the recipe to the annual Ladysmith and Cowichan Womens Institute Cookbook. This cookbook was sold in the early 1950s in the region as a fundraiser. It made its way throughout the province's communities by way of household cookery recipes shared by housewives in the 1950s, particularly via company towns. It was sold in many of the coffee shops on Nanaimo's Commercial Street, and soon became popular. Tourists in the region, especially US tourists on pleasure boats came to refer to these as "Nanaimo Bars". To most in Nanaimo and the region south of it to Duncan, however, these were originally referred to as Mabel bars, or W.I. bars. The earliest confirmed printed copy of the recipe "Nanaimo Bars" appears in a publication entitled His/Her Favourite Recipes, Compiled by the Women's Association of the Brechin United Church (1957), with the recipe submitted by Joy Wilgress, a Baltimore, Maryland native (p.52). (The Brechin United Church is in the north side of Nanaimo.) This recipe also is reprinted in Kim Blank's book Sex, Life Itself, and the Original Nanaimo Bar Recipe (Umberto Press, 1999, pp.127-29).
In 1954 the recipe "Mable's Squares" (p.84) was published in "The Country Woman's Favorite" by the Upper Gloucester Women's Institute (New Brunswick). The recipe was submitted by Mrs. Harold Payne, the daughter of Mable (Knowles) Scott (1883-1957). The ingredient list, quantities, and assembly steps closely match the recipe found on the City of Nanaimo web site.
Other unconfirmed references date the bars back to the 1930s, when it was said to be known locally as "chocolate fridge cake". Some New Yorkers claim that it originated in New York, and refer to them as "New York Slices". However, Tim Horton's coffee shops in New York sell them as "Nanaimo Bars". One modern reference even refers to the bars existing in nineteenth century Nanaimo. (Wikipedia) Another source notes: Another source notes: "These delicious bars made their reputation among people making the ferry crossing from Vancouver to Victoria. The ferry terminal on the island is in Nanaimo."
• 1/2 cup butter, melted
• 1/4 cup sugar
• 1/3 cup cocoa
• 1 egg
• 2 cups graham cracker crumbs
• 1 cup flaked coconut (unsweetened if possible, but sweetened is OK)
• 1/2 cup walnuts, chopped
*some food bloggers recommend a bit of espresso powder in the base - just sayin'
(This recipe originates before the age of food processors, but I'm thiniking you can just combine these ingredients in the processor and pulse until just combined, being careful not to chop the walnuts or coconut too much.)
• 1/4 cup butter
• 2 tablespoon Bird's custard powder (or instant vanilla pudding powder)
• 1 teaspoon vanilla
• 3 tablespoon milk
• 2 cup confectioners' sugar, sifted
• 4 ounces (4 squares or 2/3 cup) semisweet chocolate
• 1 tablespoon butter
Base Layer: Mix together ingredients. Press into a 9" square pan. Refrigerate while making filling.
Filling: Cream together butter, custard powder and vanilla. Gradually blend in milk and confectioners' sugar, alternating between additions. Filling will be stiff.
Spread over chilled base. A bent-handled (off-set) spatula dipped in water does the job. Chill to firm before adding icing.
Icing: Melt chocolate and butter together. Pour over chilled bars, tilting pan to cover evenly and smoothly. Chill well before slicing into bars.
Store in fridge.
Makes 48 bars
Photo credit: http://vinolucistyle.com/2010/02/nanaimo-bars/