I’m in the unique situation where I’m hiring my replacement after having made a promotion. I know they will make (substantially) more than me. How would I negotiate a matching or superior salary?
Everyone else is telling you to leave or try a power play, but food for thought -- you may actually be less valuable now in your new role because you aren't experienced in it. If you just moved from IC to manager, you might be a pretty new manager. It's normal for managers to have reports that make more than them. Just because you manage them doesn't make you more valuable. I'm not saying this is the case for you in…
I would also say I’m more qualified for the job than those that are applying now, so I’m not sure if this really is applicable to me.