I don't know about *best*, but White Queen of the North was my *favorite*.
Thor'Ax is called home to the White Wastes, where we find - shocker! - he is supposed to marry this albino princess type. Give the girl credit, she can wear a mini-dress in a blizzard and make it look good, but her heart is colder than the Caves of Ice. Hijinks ensue, obviously.
I always thought EVERYBODY knew this is where they stole the plot for AMOK TIME from, but the Trekkers will never admit it.