Azealia has tweeted the lyric "I GOT RACKS RACKS RACKS TILL THE ATM JAM" several times over the past few months. We knew she worked with Pharrell on a track for Beyoncé's album back in November, and we know Pharrell is featured on BWET. This may have come from the same session.
Today, she revealed it's title in a tweet - "ATM JAM"
Last year in June, Pharrell debuted the song in a performance. In the video below (around 1:25 mark) you can hear the start.
It was meant to be Swiss Beatz song, guessing Azealia now has Pharrell on the hook.