Indio, California - Billie Eilish got sentimental about her recent surprise appearance at Coachella in a sweet social media tribute bearing the caption, "greatest weekend of my life."

The post shared via Instagram on Wednesday features a snap of the 22-year-old singer alongside headliner Lana Del Rey, who welcomed Billie on stage as a special guest during weekend 1.

The two sang Lana's Video Games and Billie's Ocean Eyes together, the latter of which Billie revealed "wouldn't even exist" without the 38-year-old.

The What Was I Made For? artist has been a longtime fan of Lana's, and she's even praised her for changing the landscape for female musicians and "the potential of what is possible."

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Lana returned the favor during her Coachella set, calling Billie "the voice of our generation."

Elsewhere in her IG post, Billie shared a close-up photo of pal Odessa A'zion and some footage from inside the festival pits with model Gabbriette Bechtel.

Along with her show-stopping duet with Lana, the Grammy winner also took the opportunity to tease her new album, Hit Me Hard and Soft, during the star-studded festival.

The spicy new track, reportedly titled Lunch, appears to allude to a steamy romance with the lines, "I could eat that girl for lunch / Yeah, she dances on my tongue / Tastes like she might be the one / And I can never get enough."

The teaser came after Billie slammed Rolling Stone for leaking the album's tracklist before she could reveal it.

Hit Me Hard and Soft is set to drop on May 17.