Three layer tea looks fancy, the gula melaka sinks to the bottom, evaporated milk in the middle, tea on top. Looks like art. But that beautiful bottom layer is a thick pour of palm sugar syrup, and that is the whole reason it costs more calories than a plain teh C.
You are looking at around 210 calories, mostly because of that gula melaka. It does taste amazing, the palm sugar gives it that deep caramel thing. Just know it is a sweeter, heavier cousin of teh C, so order it as a treat and not your everyday drink lah.