World number one Iga Swiatek was able to have her cake and eat it at the U.S. Open after the Pole capped her campaign at a star-studded Flushing Meadows by collecting her third Grand Slam title.

Swiatek, who has enjoyed her brushes with New York's celebrity scene during the tournament, beat Tunisian Ons Jabeur 6-2, 7-6(5) on Saturday to claim a massive $2.6 million winner's check.

However, tournament organisers had another reward for her, hiding a piece of tiramisu - one of her favourite treats - inside the trophy.

"I really appreciate it. Especially since I didn't have anything to eat," she said.

The two weeks of competition could scarcely have been sweeter for the Pole, who balanced her usual on-court seriousness with off-court fun.

She grabbed a photo with her idol Serena Williams, rubbed shoulders with Olympic gold medallist Lindsey Vonn and swooned at the sight of singer Seal.

"Actually after I met Seal, I was like, 'Even if I'm going to lose right now I already won this tournament, because I got photo with him,'" said Swiatek.

"It's something that it's only going to happen probably in New York - yeah, because it's New York."

Swiatek, who has also won two French Open titles, fit right in with the city's boisterous fans and was greeted on the Flushing Meadows plaza for an ESPN interview with a roaring crowd of her compatriots after becoming the first Polish woman to win the tournament.

"The energy that they give me, it's surreal," she said.