You may recall seeing Mariah Carey’s NYC penthouse on an episode of MTV Cribs —or, perhaps in a 2001 Architectural Digest spread . And now, the “We Belong Together” singer’s pad has landed on the market for $27 million. The songstress bought two units spanning three floors at the top of Tribeca’s Franklin Tower in 1999, transforming them into a 12,700-square-foot single residence with eight bedrooms and seven-and-a-half baths. Before moving in, Carey hired designer Mario Buatta to create a home fit for a diva, and he delivered. Silver-leaf doors, bronze-inlaid limestone flooring, lacquered walls, and butterflies galore. “We put them wherever we could,” Buatta explained to AD in 2001. “There are butterfly handles on the cabinets in the bedroom, and butterflies are woven into the bed hangings. They’re even on the soap in the bath and on the tiles in the kitchen. There are so many butterflies in this apartment, you don’t even notice them.…