Sharing a snapshot of the delicious-looking creation, which was covered in hundreds and thousands, the doting mum wrote: "Someone was up late baking [laughing face emoji] Lovely surprise @cruzbeckham."
WATCH: David and Victoria Beckham surprise son Cruz with amazing birthday cake
Clearly suspicious, Victoria also teased: "What are you after?" Cruz replied with a laughing face and a red heart emoji.
The heartwarming post comes shortly after it was reported that Cruz and his girlfriend Bliss Chapman have gone their separate ways. According to the Mirror, Cruz, 17, and Bliss - daughter of model Rosemary Ferguson, a friend of Victoria's - have ended their fledgling romance after 18 months together.
Given the families' close ties, the split is sad news for all involved; Victoria and David are said to have really liked Bliss. But, no doubt, they will be able to maintain their friendships.
Victoria was impressed with her son's culinary skills
While Cruz has been unlucky in love, the same cannot be said of his eldest brother, Brooklyn Beckham. The 23-year-old is set to marry his fiancée Nicola Peltz this spring; while the date is not known, reports have indicated that it will take place in April at Nicola's family's holiday home in Palm Beach, Florida.
Both David and Victoria Beckham are doting parents to four children; Brooklyn, 23, Romeo, 19, Cruz and ten-year-old sister Harper. In an interview on Jimmy Kimmel Live!, Victoria spoke about her large brood, saying: "It's a lot of kids. I always say it's less about parenting and more about crowd control when it gets to that many, right?"
David and Victoria with their four children
She added: "All four kids bring all their friends over to the house, so when we come home at the end of the day there's always lots and lots of children."
How does she control them all? "I think the main focus is making sure that they all leave empty-handed and that the art is still on the wall!"
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