William and Kate took off their coats, put on aprons and picked up large rolling pins as they tackled the task, to keep up with orders at a market trader in Pontypridd, South Wales.
Staff at The Welsh Cake Shop will be working through the night this week to fulfil orders, and they drafted in the royal couple to help out when they visited the town to learn how the community is coping after recent devastating flooding.
The prince and princess rolled out the dough, made ahead of time, as William asked shop owner Theresa Conner, who had shown the couple the process: "Is it thick enough?"
William and Kate's skills were honed when they appeared with TV baking queen Mary Berry on A Berry Royal Christmas show, and William praised her influence.
With flour stuck to the sleeve of his maroon sweater, William smiled and said: "Well I don't know, my stunning baker skills, Mary Berry taught me everything I need to know."
The couple cooked their cakes on a hot plate, keeping a watchful eye on them and turning them after five minutes, and Madison Conner, daughter of the shop owner, gave them the seal of approval.
"They're perfect, they're great - they're bangin," she said.
Conner praised the couple's efforts with the rolling pin, saying: "They were very good at baking.
"For us ahead of St David's Day, it's a real privilege to meet them and have them visit us."
Some of their cakes were served up when the prince and princess sat down in the neighbouring Fountain Cafe and chatted over a mug of tea with market traders and other businesses about Storm Bert, which struck in late November bringing widespread flooding to Pontypridd when the River Taff burst its banks.
The town, which was badly hit by Storm Dennis in 2020, was also in the path of Storm Darragh, which brought extremely high winds to the region a few weeks after Bert.
One trader told their royal guests the regularity of the storms made them "feel like sitting ducks".
Before leaving the couple went on a walkabout meeting dozens of well-wishers who had braved heavy showers to catch a glimpse of the royals.
There were a few protesters among the crowds, with one carrying a banner which read "We don't need handshakes, we need flood justice".
The future King and Queen heard how the community had come together to help repair the damage caused by the storm.
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