This performance was just one of the best award show performances I've ever seen by either of them.

It's from the 1998 MTV VMAs. I remember watching it back then. Part of the stage (stage right) actually looks like the little flourish on the symbol.

NOTE: The audio of this video is actually from her performance on The Oprah Winfrey Show the same year. The overdub is well done by the person who posted the video, but not the original from the award show.

Here's the original MTV VMA performance with original audio.

Here's the Oprah performance, where the audio is taken.