Here's the recipe for Nanimo Bars, straight from Jeremy's grandma. I tweaked some of the ratios a bit since her original recipe called for a 9x9 pan and I didn't have one.
In the microwave or double boiler melt
1/2 c. butter
1/4 c. sugar
1 tsp vanilla
5 Tbsp cocoa
Cool the mixture slightly and add one beaten egg.
2 c. crushed graham crackers
1 c. coconut flakes
1/2 c. chopped walnuts
Combine both mixtures and press into a 9x13 pan.
4 c. powdered sugar
1/4 c. milk
2 Tbsp Birds Custard Powder (this may not be at your local grocery but it is available online, and for sure in Canada, ha ha. If you don't want to get the powder Kate says she uses vanilla pudding and can't taste a difference, but my MIL says she can taste a difference. So... I wouldn't know, I haven't tried the pudding version. I'm just givin' you guys options)
1 c. butter
Spread frosting on top of crust and chill. Melt 8 squares of semi-sweet chocolate (if you like dark you can use that instead) and 2 Tbsp butter. Mix and spread on top of the frosting mixture and chill until set.