dumbfounded
It's dumbfounding to me that they are just ignoring the issue.
If we accept these facts, the defendant's denial is dumbfounding.
The latest revelations in the paper are dumbfounding.
The economy is still growing at a dumbfounding rate.
The country is poor, but has areas of dumbfounding beauty.
This is the latest work from a director of dumbfounding brilliance.

SMART Vocabulary: related words and phrases

Surprising and shocking
against all expectationsphrase
amaze
amazing
amazingly
astonish
dumbfoundingly
dynamite
earth-shaking
earth-shattering
earth-shatteringly
pull
pull something out of the bag/hatidiom
raise (a few) eyebrowsidiom
reality check
sensationalist
turn-up for the book(s)idiom
unbelievable
walk
walk in on someone
world-shattering