Co-owner David Brice was thrilled his firm was invited to mark the special birthday.
He said: "For such a huge occasion, for Truly Scrump-tious to have been selected is a great honour."
Finishing touches were made to the giant birthday cake by head designer Paul Bradford on Tuesday at their Braehead Road production studio.
In the style of a giant picture frame, with tartan, thistle and saltire decorations, it includes photos of all 141 children who share their 10th birthday with the parliament.
Erica Oxley of Linlithgow Bridge was a special guest at the party, one of more than 100 children born on the same day as the Scottish Parliament.
The 10-year-old was joined by her brother Andrew and her parents at the party along with other VIP - the Queen. Mum Alison said Erica had looked forward to the day, but was ''a bit overwhelmed'' by the significance of it all.
Find out more about the Parliament and its history here
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