Been making Nanaimo Bars for more than 50 years (I was 10 when I made my first batch); the recipe came from the sugar package and it did call for walnuts. I switched to pecans about 25 years ago and most people seem to like that better. I dislike almonds so have not tried this version. Bird's custard powder gives a subtle flavour and colour to the icing (middle layer) that vanilla custard powder doesn't give - I can always tell the difference.
I have made many of the variations: mint, orange, lemon, etc. especially when I've made Nanaimo Bar for weddings, showers, or special birthday parties - I usually do one original and one or two different flavours, depending on how many are required.
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