Paris Hilton -- Ibiza's Missed My Ass ... Let the Foam Begin! (PHOTOS)

Paris Hilton made a triumphant -- and soaking wet -- return to her summer home ... reminding us why they keep paying through the nose to bring her back to Ibiza.

Hilton was the main attraction Saturday night at Amnesia's Foam & Diamonds party, where she'll be DJing every Saturday night for the next few months. We're told the club owner said last weekend's opening party was the biggest money maker, so far this summer.

Paris' millionaire BF, Thomas Gross was there, and bought out the entire VIP balcony for himself and friends. Not to be outdone, we're told someone from Dubai came in and dropped $100k on endless bottles of Cristal.

The party went on til 7:30 AM and was capped off when Paris doused the crowd with foam from above. But the most fun part for Paris had to be the paycheck. We hear she's getting $300k per gig!

Saturday nights are way more than alright for P.