Jessica Simpson is lovin' the way she looks ... posting another bikini picture from her vacation in Cabo after she dropped 100 pounds for the 3rd time!
The "Open Book" author posted a mirror pic from what seems to be her hotel room in Cabo San Lucas Monday ... rocking a cheetah print 2-piece for the camera.
She's been living it up with her family in Mexico for spring break, posting photos with her husband Eric Johnson, and their children -- 9-year-old Maxwell, 8-year-old Ace, and 3-year-old Birdie Mae.