Two of the most famous giant asses in the history of booty came together in Vegas over the weekend -- Blac Chyna and Alexis Texas ... in an event that woulda made Sir Mix-A-Lot blush.
For the unfamiliar ... Alexis is one of the all time porn legends -- who just won "Most Epic Ass" at the 2017 AVN Awards.
And as you can tell by the photos, Chyna couldn't keep her hands off it when they got together at the Sapphire Pool & Dayclub party in Vegas over the weekend.
Butt respect Butt.