Crucible

Crucible by Troy Denning
Forty years after Return of the Jedi, Luke, Han, and Leia go on one last adventure together, facing off against twin geniuses with a taste for evil experiments and a hunger to dominate the galaxy through corrupt corporate expansion.

Buy from Amazon!

This is a post-Return of the Jedi novel from the Legends timeline. Think of it as an alternate universe from the sequel movies and newer books.