Simon Cowell's fiancée threw him a surprise party in celebration of his 56th birthday over the weekend.

Simon Cowell's 56th birthday bash (c) Instagram

Simon Cowell's 56th birthday bash (c) Instagram

The music mogul reached the milestone on October 7 and marked the occasion with a lavish bash, arranged by his lover Lauren Silverman, at the Sur restaurant in West Hollywood with a handful of his close celebrity friends.

'Real Housewives of Beverly Hills' star Lauren Vanderpump, who owns the glamorous eatery in California, was in attendance along with TV host Ryan Seacrest and fashion designer Rachel Roy, according to gossip website TMZ.com.

Despite the sophisticated arrangement, things soon turned funny when Simon was gifted a miniature car by his pal and 'American Idol' co-star Ryan, 40, who pokes fun at the judge's height, and began whizzing around the venue on it.

Taking to his Instagram account on Monday (12.10.15), the TV host shared a photograph of Simon sitting on the tiny Maybach convertible, while he controlled it with a remote.

He wrote: "Found Simon a Maybach in his size."

Meanwhile, the 'X Factor' judge's new mini vehicle comes just a few days after he admitted he'd like someone to buy him a miraculous flying car for his birthday.

He said recently: "I would like a flying car. I saw one and I read about it in 'Top Gear' recently. I thought, 'God, if there is anything I want, that is it'.

"It is the coolest thing. If they can make one, that would be top of my list. I want the flying car. I'm easy to buy for."