But of course cake wasn’t all they ate - guests were also served canapes, included Scottish langoustines, grilled asparagus and croquette of confit lamb.
Pol Roger champagne was flowing, alongside soft drinks and elderflower cordial which is made on the estate.
Speeches were made by both Harry and Prince Charles - one guest telling how Harry spoke about Meghan and called her his wife for the first time.
"He was talking about his wife and you know everybody was clapping because it was the first time he was using that term for Meghan so it was really nice.’’ she said.
People magazine reported Prince Charles gave a heartfelt speech. “He ended it calling him, ‘My darling old Harry, I’m so happy for you,’' a guest said.
A smaller evening reception, hosted by the Prince of Wales, is now underway at Frogmore House.
The event will be a private event, allowing the guests to relax and let their hair down with the happy couple - and as for the speeches, the newly minted Duchess of Sussex is expected to speak.
James Corden is the MC for the event.
Wonder if Harry will do any carpool karaoke!