Recipe provided by Mike Jankulak (firstname.lastname@example.org).
For the first layer, you need 1/2 cup butter, 5 tbsp sugar, 5 tbsp cocoa, 1 tsp peppermint extract, 1 egg, and 2 cups finely crushed graham cracker crumbs (plain). Melt the butter in a saucepan, then add everything except the crumbs. Cook it all until the mixture gets (in mom's words) "a little custardy" and then remove from heat and add the crumbs. Press into an 8" x 8" pan. Now, I greased the pan with some butter first (to make my life easier later on), and I left the butter melting/bubbling a bit too long because Ilona called and was telling me about her coming-out. Oh, and I doubled the recipe and made it in a 9" x 13" pan, but I wouldn't recommend that unless you're bringing it to feed the Murriken jackals at work, like I did.
For the second layer, you need 1/4 cup butter, 1/2 cup vanilla pudding (my mom substitutes 2 tbsp powdered Jell-o vanilla pudding mix and 3 tbsp milk, and so did I), and 2 cups of icing sugar (Murrikens seem to call this "confectioner's sugar" (snort)). Cream the butter and add everything else in such a way so as to end up with a smooth icingish consistency. Spread evenly on top of the first layer. It will make your life easier if you refrigerate these first two layers for a hour or so before you add the third, but I didn't because it was 11pm and I wanted to go the bed more than I wanted to make perfect Nanaimo Bars. Besides, nobody at work had ever heard of the things before, so who's to know if I fucked them up?
The third layer is 2 oz unsweetened chocolate and 1 tbsp of (you guessed it!) butter. In my doubled version, I got through almost a whole pound of butter before I was done. My mom substitutes the same amount of semi-sweet chocolate chips (by weight) for the unsweetened chocolate, and I was tempted (who wants to eat unsweetened chocolate?), but in the end I went with the recipe, and it turns out that the first two (thicker) layers are more than sweet enough to compensate. Melt this stuff together and spread on top of the first two layers (if they've been refrigerated, there's less chance of mixing the chocolate in with the icing). It should make a very thin layer that completely hides the icing, but only just.
Refrigerate the whole thing, and keep it refrigerated if you don't serve it all at once. Use a sharp knife to cut them into squares (1" - 2" square) so you don't crack the surface too much. If it turns out well, remember to tell everyone it's Canadian. If it doesn't, pretend you bought it at a store.