How to drink all the tea from a cup
Of course
The mutt will always be below
Unless you shake it and get it to the top
And also it will be of the same shape as the liquid
(This is our key idea.)
So you tilt the glass, so you get the shape of a triangle.
You're still only drinking from the top
Until You reach the first mutt
Also, the shape of the triangle was elongated for a reason
[volume remains the same, but length differs]