Unsurprisingly, the two couldn't keep their disguises up for too long.
Fans weren't fooled, quickly recognising the two as who they really are.
"Hey guys I'm here at the 50th Street subway station right below Rockefeller Center, and Miley Cyrus and I are about to go onto the subway platform and start [performing] in disguise. Nobody knows that this is going to happen, and nobody knows that it's Miley Cyrus," Jimmy begins. "Alright Bart, let's party!" Miley responds, referencing Jimmy's character name.
They started performing Miley's godmother Dolly Parton's iconic tune "Jolene" and as if people wouldn't recognise that?!
She then burst into "Party in the USA" and we are so jealous we weren't there.
Watch the whole thing below and fall even more in love with Miley: