Is the way to pull a shape and twist it slightly.

This one has me stumped.  I cannot figure out a way to draw this using any technique, even some "round about method" using planes and splits.

Simple example problem: 

Draw a square 20mm on a side.

Pull that square 30mm away from the original AND twist the new square 45 degrees from the first.

The finished object needs to be a solid.  I realize the sides will be curved.

The example below is the closest I could do using a VERY rough approximation by stacking multiple squares and twisting each one slightly above the one below it.  This is NOT what I am trying to achieve, but it does give an approximation of the twist, somewhat.  the corners should be relatively straight lines, not stairsteps.  I realize the edges and corners will curve.

Another way to approach this would be to draw a square, pull it to the desired height, then somehow ANCHOR the bottom so it won't move, a apply the required rotation to the top surface,  This would twist the object.  I can't find a way to anchor anything in DSM so it does not move, while other parts are pulled or rotated.

Anyone have any thoughts or suggestions?