Tips: These incredibly rich, no-bake bars are named after a city in British Columbia, though no one seems to know why. They are simple to prepare, though they must chill at least 2 hours after you make them. My version includes grated orange rind in the buttercream filling, but it can be omitted, if you wish. Store the Nanaimos airtight in the fridge for up to five days, or freeze them for longer storage. If you store them in plastic cartons, as I do, place them in a single layer, and tape a piece of paper towel on to the underside of the container top to absorb any condensation, which might otherwise drip back into the cookies. If you freeze them, make sure the wrappings don't touch the glaze.

You can use supermarket-bought chocolate here, if you wish, but I have made these both with supermarket chocolate and good-quality semisweet, and the difference is like night and day. You'll need a food processor, blender, or nut grinder for the walnuts. Traditionally, by the way, the "glaze" is a topping of melted chocolate and butter, but I find a ganache easier to cut and nicer to eat.

Crust:

Line an 8 inch square baking pan with heavy-duty foil (or two lengths of regular aluminum foil); the foil should extend at least to the top of all sides (fold any overhang back against the outside of the pan).

For Crust: In food processor fitted with steel blade (or use blender or nut grinder), process walnuts just until finely ground (if using food processor or blender, grind the nuts with a few spoonfuls of the graham cracker crumbs to help prevent over-processing). Be careful here-- you don't want walnut paste! In medium bowl, combine ground walnuts and all graham cracker crumbs and mix well.

Place chopped chocolate and butter pieces in small heatproof bowl. Place over simmering water on low heat; stir often until melted and smooth. Remove from heat and hot water. Add to walnut-crumb mixture; with spoon, mix thoroughly until all ingredients are well-blended. Turn mixture into lined pan. Compact firmly onto bottom of pan. Chill while preparing Filling.

For Buttercream Filling: In medium bowl, beat softened butter with hand-held electric mixer at low speed just until creamy. Add half of confectioners' sugar and 1 Tbsp. milk. Beat in at low speed. Scrape bowl and beater(s) well with rubber spatula. Add remaining half of confectioners' sugar and vanilla. Beat in at low speed, then increase speed to medium-high and beat until fluffy. Gradually add enough remaining milk for a good spreading consistency; you don't want this Filling too stiff, but it shouldn't be runny, either. Remove from mixer; by hand, stir in orange zest.

Place all of Buttercream Filling on top of chilled Crust. With back of spoon or offset spatula, spread as evenly as possible. Chill while preparing Glaze.

For Glaze: Place finely chopped chocolate and salt in medium heatproof bowl. In small heavy-bottomed saucepan, heat cream over low heat, stirring occasionally, just until it simmers. Remove from heat. Add about two-thirds of hot cream to chocolate. Allow chocolate to stand for a minute or two, then stir or whisk gently until smooth. If necessary, place chocolate over simmering water on low heat (water should not touch bottom of bowl); stir often until smooth, then remove from heat and hot water. Gradually add remaining cream to melted chocolate mixture. Glaze will be thin at this point.

Cool Glaze at room temperature, gently whisking or stirring occasionally. Scrape sides and bottom of bowl with rubber spatula occasionally. When a small amount of Glaze dropped from a spoon back into the bowl forms a slight mound which remains for several seconds before disappearing back into the bowl, the Glaze is ready. Turn cooled Glaze onto surface of Buttercream Filling; immediately spread evenly with back of spoon or offset spatula. Return Nanaimos to refrigerator; chill at least 2 hours before cutting.

To cut, remove block of uncut cookies, still in foil, from pan. Allow to stand at room temperature about 10 minutes before cutting. With small, sharp knife, gently separate Glaze from foil. Carefully peel foil from edges of bars. Use a large, sharp, straight-edged knife to cut bars; frequently, it will be necessary to rinse the knife blade clean under hot water, then dry it, if the cuts are to be kept neat. Cut into 24 bars (make sure you cut all the way through the crust when cutting). Store in refrigerator as described above, or freeze. To serve, allow to stand at room temperature 10 to 15 minutes before eating.

24 bars