Model behavior! Gigi Hadid celebrated her recent 21st birthday by devouring a burger during her appearance on The Tonight Show Starring Jimmy Fallon on Monday, May 16.

Fallon, 41, surprised the supermodel with a belated gift — her “favorite” burger from NYC eatery JG Melon. Hadid said she declared it the winner after trying a new burger every week with her best friend during her first year living in New York.

Although she has to eat healthily to maintain her model physique, she says she lives by the slogan “Eat clean to stay fit. Eat a burger to stay sane.” She admitted she just had one for dinner Sunday night, but the fashionista still chowed down on the delicious patty, which she loves because “they don’t try too hard” and “it comes with all the veggies.” 

The beauty also talked about her birthday celebrations in Las Vegas, where she tried her hand at gambling. Although boyfriend Zayn Malik wasn’t able to attend, he did prepare her for the big night. “You have to do Vegas on your 21st birthday. My boyfriend taught me how to play poker the night before I went to Vegas,” she said before correcting herself that she meant blackjack, but slipped up because of her nerves. The model also revealed she won $400 on the $15 blackjack table, but will probably stick to Monopoly from now on.

While she may have partied it up later in Vegas and at her big bash at the Nice Guy in L.A., she spent the actual day, April 23, with her tight-knit fam. “On my actual birthday, I spent it at the beach with my family, so I didn’t actually drink on my 21st,” she said. 

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