allow users to post w/o dashboard access

I’m trying to create a site for registered users only who would be able to add posts on the frontend, without access to the dashboard.

So they would see a link in the sidebar, for example, saying “Add new post” and they would be able to post something right there, much like leaving a comment.

I’ve been looking around at plugins, but most seem to create a parallel login system or to be full-blown stand-alone social networks (which is too heavy for what I’m trying to do).

Any thoughts? Thanks!