Liza Minnelli -- My Fans Are a Total Drag!

After two sold out concerts on Fire Island in NY last weekend, Liza Minnelli totally wigged out ... at a drag queen competition!!!

Sources tell us ... the 66-year-old gay icon stopped into Cherry's bar, ordered up some fried chicken fingers and got on stage during Miss Cherry's drag queen competition. We're told the surprised crowd went nuts ... chanting "Liza! Liza! Liza!"

When not taking photos with fans and female impersonators like Logan Hardcore, Ariel Sinclair, Gusty Winds and Bianca Del Rio, we're told Liza hit up the Rainbow Dreams boutique -- sans makeup -- and spent some serious coin on sequin hats, boas and even a pack of smokes.