There's really no way out now. They've painted themselves into a corner by four decades of empty threats against a regime that recognizes them for exactly what they are.
Sanctions don't work with a leadership that's nuts and has little stake in the welfare of their own citizens. Never have, never will.
So, to (sorta not) answer your question, I don't really know how to recover from the complete failure the UN has created. What I do know is that, when you find yourself in a hole, stop digging. We pissed away our chance at winning a shooting war back in the 50's, so I'd probably go with a hugs-n-kisses leftie response and throw open the doors and hope for the best. It's not like DPRK can get any more dangerous, and we're clearly not doing a good job keeping them from anything (listen to the KABOOMs), so about the only angle left is a barrel of carrots. It's a crappy solution, but the UN is just embarassing themselves by continuing to screw the pooch with empty words.