Jessica, who quit The Only Way Is Essex in February, attended a party thrown by Manuka Doctor and was lucky enough to grab a selfie with the US reality star.
Keeping Up With The Kardashians' Kourtney, who last night walked the red carpet at the Glamour Women Of The Year Awards, has been made Global Ambassador of the brand and the bash was held in her honour.
Sharing her selfie on Instagram, Jess was quick to tell fans how nice - and gorgeous - Kourt is in the flesh!
Jessica gushed: "With the gorgeous @kourtneykardash at the @manukadr evening. She was so lovely & super hot!"
Meanwhile, earlier today, Kourtney's sister Khloe appeared on The Ellen Show in the US and the girls caught up with each other live on air.
We all know how much American's love the UK, so we bet the audience and viewers at home enjoyed listening in to hear what Kourtney has been up to in London!
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