Then I put treats in two drawers and Penny had a go. (Wasn't she a good girl to wait so patiently?)
Next Penny waited again
while I placed treats in every drawer
and closed the drawers.
After which her patience was rewarded and she successfully conquered all the drawers.
She had the rest of her evening meal from the toy. Next time, I'll put one a 'stopper' in one of those top holes and see if she can figure out how to pull it out so the drawer can move.
I prefer the wooden version, even though the plastic version can be cleaned and this one can't.