J Lo went all out for her twins' 10th birthday party ... and she took REALLY good care of the people who helped throw it.
Jennifer put on a bash for more than 30 guests at the Sugar Factory in Las Vegas Thursday night to celebrate Max and Emme's bday. We're told the party arrived around 5 PM and threw down for FOUR hours ... and made good use of their time.
Well-connected sources tell us the bill was $7,500 and included custom cakes for each child -- red velvet Mario Bros. cake for Max and chocolate sloth cake for Emme. They also gorged on virgin gummy worm goblets, and a King Kong Sundae ... with 24 scoops of ice cream topped with sparklers!
We're told J Lo had a blast dancing and spoiling her kids, solo. Their dad, Marc Anthony, wasn't there ... and ditto for A-Rod. We know she was happy about the whole production, because she tipped $5,500!!