I had to chuckle when I heard that this was the most popular dessert at the Vancouver Olympics. My recipe is so old the paper has yellowed! We've been eating Nanaimo Bars for a long time, and yes, they really did originate in Nanaimo, BC.
When I make them, it's pretty much an all-in-one-go type of process. Each layer chills while the next is made, although adding the chocolate on top can make the middle messy if it hasn't chilled enough.

Here you go, the original recipe.

Bottom:
1/2 cup melted butter
1/4 cup sugar
5 tbsp cocoa powder
1 tsp vanilla
1 egg
2 cups graham wafer crumbs
1 cup coconut
1/2 cup chopped walnuts
Mix the first five ingredients together (butter, sugar, cocoa, vanilla, egg) so that it resembles custard. Add remaining ingredients and mix well. Press into an 8"x8" pan. Chill.

Filling:
1/4 cup butter
3 tbsp milk
2 tbsp vanilla custard powder (Bird's Eye)
2 cups icing sugar
Make an icing by creaming together filling ingredients. Spread onto chilled bottom layer. Chill.

Icing:
4 oz semi-sweet chocolate
1 tbsp butter
Melt together over hot water. Pour and spread evenly over chilled filling. Chill well.
Cut into squares and serve.

Have two questions, hope I dont sound stupid. Is icing sugar powdered sugar? Also never heard of custard powder?

I 'm sure the icing sugar is like our powder sugar. And I haven't heard of custard powder either. So it isn't a stupid question. Elaine

Too funny. I always thought everything was available in the USA!

Yes, icing sugar is powdered sugar, otherwise known as confectioner's sugar. Certainly you have that!

Custard powder is, well, powdered custard. Here's a picture of what I'm talking about. Also, I checked on-line and found that vanilla pudding mix can be used as a substitute. I've never tried it, so can't say what kind of substitute it would be.

I will look for the custard powder, its very possible we have it I just have never heard of it, I'll let you know what I find.

I too have beem making these for many years, used to live in Manitoba. Vanilla pudding mix is what I use.

Ok another numb question do you use the instant pudding? Thank you for all of your help

I use it the same as the custard powder, cream it with the other ingredients. The downsize to using the pudding is you are left with a box of 'not enough to make pudding with', so you have to make another batch of Nanaimo Bars to use it up! One would not want it to go to waste LOL! (It does keep in a baggie).

I'm anxious to try them, how do they freeze or have you ever froze them? Its just DH and myself but could share with the neighbors, if they freeze well I will take them for a Easter Party that we always go to at DD in-laws.
Thanks for your help

Good question. I have never frozen them, but I can't think of why they would not freeze OK. I have kept them in a metal tin for about a week, in the refrig.