I thought she was referring to the shape with the double T.
Since T is usually pronounced pretty much the same by the Japanese (ティ not チ) I don't think she was using it as a replacement for the first syllable in chinpo.
Calling them T's because of their shape is a whole lot more funny and creative than the other interpretation in my opinion lol.
@RonBWL I got you. People were still asking after the fact though, so pointing it out directly seemed the best way to get the joke across. Didn't get the sense it was meant to be cryptic, my bad on that.