2 ways i hit out of hard bunkers...

use your lob wedge and really hit down behind the ball hard to get the clubface into the sand.

or,

use your lob wedge and play a shot like u are hitting off fairway grass.. you know the club won't dig into the sand, so try hitting it like a normal short high chip. don't take any of the sand until after you've hit the ball.

expect the ball to run... it won't spin.