Kim Kardashian Hits Malibu Beach in Spectacular Beige One-Piece for SKIMS Photo Shoot

Kim Kardashian is back on a beach famously populated by celebrities, and last Friday she was the undisputed queen of the Bu.

Kim was on the sands of Malibu for another photo shoot ... it seems it's for SKIMS swim line.

The 42-year-old billionaire mogul is in INSANE shape ... thanks to two-hours of daily training. Her personal trainer, Senada Greca, needs only these pics to fill her client list.

It's a super sexy shoot ... btw, she went back to the scene of the crime, where she posed in the jaw-dropping pink bikini.

Now there are always naysayers ... yeah, she's rich, has the ability to set her own schedule, hire a trainer -- yada yada yada -- but it takes commitment and she's clearly doubled down on that.