The Nedlands resident won two firsts and a third at last year's cookery exhibition but his late wife's top-secret relish recipe earned him the prize closest to his heart.
"Over the years we have lived in various houses with orange or lemon trees, so I started making jams just to save the fruit that dropped on the ground," Mr Hopkins said.
"In 2010 I thought:"Let's slip a couple of jars into the show and see what happens"
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"They said my marmalade was"slightly burnt", which hit me quite hard. It took me a while to get confident enough to go back and tackle it again."
A year after his wife's death, Mr Hopkins entered his tribute Grandma's Relish, orange cognac marmalade and mustard in the 2014 Perth Royal Show.
"I nearly fell over when her relish won first prize," he said.
"My five children and 11 grandchildren ask for it all the time; they are the ultimate taste testers. At the end of the day it's all about having fun, being innovative and making something that you like."
Mr Hopkins said he had created some new flavour combinations for this year's competition.
The Perth Royal Show runs from September 26 to October 3.