Authentic Nanaimo Bars - cooking recipe

Ingredients

1/2 cup unsalted butter (NO substitutes)
1/4 cup granulated sugar
5 tablespoons cocoa (sifted to get the lumps out)
1 large egg, beaten
1 3/4 cups graham cracker crumbs
1 cup coconut
1/2 cup almonds, finely chopped
1/2 cup unsalted butter (no substitutes)
3 tablespoons cream
2 tablespoons custard powder
2 cups icing sugar
4 ounces semi-sweet chocolate baking squares (4, 1 oz each)
2 tablespoons unsalted butter

Preparation

Bottom Layer'.
Melt first three ingredients in the top of a double boiler.
Add egg when the butter and cocoa are warm (not hot) and stir hard to cook and thicken and not let the egg scramble .About 1 minute is good.
Remove from heat.
Stir in crumbs, coconut and nuts.
Press firmly into an ungreased 8 X 8 pan.
Second Layer:
Cream butter, cream, custard powder and icing sugar together well.
Beat until light.
Spread over bottom layer.
Third Layer:
Melt chocolate and butter over low heat.
Cool.
Once cool enough to not melt the middle layer, but still liquid, pour over second layer, tilt pan so it is evenly covered and chill in refrigerator.