According to The Sun, the Bajan babe sent Adele the pink iced boob sponge to her home in North London on Saturday (5th May), accompanying the treat with a saucy message, which RiRi later tweeted.
The Where Have You Been singer wrote on Twitter: "Happy Birthday to my lover, Adele” - followed by a topless snap of RiRi covering the iced breasts with her hands.
Rihanna then added: "To Adele Laurie Blue Adkins, the baddest b*tch around. Have the best freaking Bday. Cake cake cake xxx”
As well as receiving the cheeky cake from RiRi, the Rolling In The Deep singer reportedly spent her big day with boyfriend Simon Konecki - with The Sun reporting the couple drank boxes of wine with friends at her London pad.
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