Mario Dedivanovic, beautifier to Kim Kardashian West and the rest of the 'klan', took to Instagram on Sunday (8 March) to share his trick.
With Kendall recently nabbed as the face of Estée Lauder, we imagine Mario's been working his way through the brand's entire range!
But there's one product that's stood out from the rest, for the make-up maestro.
Alongside a glam snap of Kendall, Mario commented: 'Make-up tip. For a sheer to medium coverage foundation, try Invisible Fluid Make-up by @esteelauder. It builds and blends very nicely #MakeupByMario.'
He's right about the foundation's, £28.50, imperfection-banishing powers and its lightweight, oil-free formulation makes it a good'un for oily skins especially.
Mario's got some other weapons in his foundation arsenal too.
He's previously used Giorgio Armani Luminous Silk Foundation, £36.50, on Kendall - another great choice for skin that's prone to shine.
Urban Decay Naked Skin Weightless Ultra Definition Liquid Make-up, £27, was the gem behind Kim's gorgeous complexion for her wedding with Kanye West. With special light-reflecting properties, it has the ability to make you look airbrushed. Nice!
Kim K's also a fan of NARS Sheer Glow, £31. Despite the name, this one's actually gives pretty full coverage with plenty of radiance thrown in too.
What's your all-time favourite foundation?
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